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authorNorbert Preining <norbert@preining.info>2019-09-02 13:46:59 +0900
committerNorbert Preining <norbert@preining.info>2019-09-02 13:46:59 +0900
commite0c6872cf40896c7be36b11dcc744620f10adf1d (patch)
tree60335e10d2f4354b0674ec22d7b53f0f8abee672 /systems/texlive/tlnet/tlpkg/tlperl/lib/CPAN.pm
Initial commit
Diffstat (limited to 'systems/texlive/tlnet/tlpkg/tlperl/lib/CPAN.pm')
-rw-r--r--systems/texlive/tlnet/tlpkg/tlperl/lib/CPAN.pm3997
1 files changed, 3997 insertions, 0 deletions
diff --git a/systems/texlive/tlnet/tlpkg/tlperl/lib/CPAN.pm b/systems/texlive/tlnet/tlpkg/tlperl/lib/CPAN.pm
new file mode 100644
index 0000000000..1f69119e5f
--- /dev/null
+++ b/systems/texlive/tlnet/tlpkg/tlperl/lib/CPAN.pm
@@ -0,0 +1,3997 @@
+# -*- Mode: cperl; coding: utf-8; cperl-indent-level: 4 -*-
+# vim: ts=4 sts=4 sw=4:
+use strict;
+package CPAN;
+$CPAN::VERSION = '2.20';
+$CPAN::VERSION =~ s/_//;
+
+# we need to run chdir all over and we would get at wrong libraries
+# there
+use File::Spec ();
+BEGIN {
+ if (File::Spec->can("rel2abs")) {
+ for my $inc (@INC) {
+ $inc = File::Spec->rel2abs($inc) unless ref $inc;
+ }
+ }
+ $SIG{WINCH} = 'IGNORE' if exists $SIG{WINCH};
+}
+use CPAN::Author;
+use CPAN::HandleConfig;
+use CPAN::Version;
+use CPAN::Bundle;
+use CPAN::CacheMgr;
+use CPAN::Complete;
+use CPAN::Debug;
+use CPAN::Distribution;
+use CPAN::Distrostatus;
+use CPAN::FTP;
+use CPAN::Index 1.93; # https://rt.cpan.org/Ticket/Display.html?id=43349
+use CPAN::InfoObj;
+use CPAN::Module;
+use CPAN::Prompt;
+use CPAN::URL;
+use CPAN::Queue;
+use CPAN::Tarzip;
+use CPAN::DeferredCode;
+use CPAN::Shell;
+use CPAN::LWP::UserAgent;
+use CPAN::Exception::RecursiveDependency;
+use CPAN::Exception::yaml_not_installed;
+use CPAN::Exception::yaml_process_error;
+
+use Carp ();
+use Config ();
+use Cwd qw(chdir);
+use DirHandle ();
+use Exporter ();
+use ExtUtils::MakeMaker qw(prompt); # for some unknown reason,
+ # 5.005_04 does not work without
+ # this
+use File::Basename ();
+use File::Copy ();
+use File::Find;
+use File::Path ();
+use FileHandle ();
+use Fcntl qw(:flock);
+use Safe ();
+use Sys::Hostname qw(hostname);
+use Text::ParseWords ();
+use Text::Wrap ();
+
+# protect against "called too early"
+sub find_perl ();
+sub anycwd ();
+sub _uniq;
+
+no lib ".";
+
+require Mac::BuildTools if $^O eq 'MacOS';
+if ($ENV{PERL5_CPAN_IS_RUNNING} && $$ != $ENV{PERL5_CPAN_IS_RUNNING}) {
+ $ENV{PERL5_CPAN_IS_RUNNING_IN_RECURSION} ||= $ENV{PERL5_CPAN_IS_RUNNING};
+ my @rec = _uniq split(/,/, $ENV{PERL5_CPAN_IS_RUNNING_IN_RECURSION}), $$;
+ $ENV{PERL5_CPAN_IS_RUNNING_IN_RECURSION} = join ",", @rec;
+ # warn "# Note: Recursive call of CPAN.pm detected\n";
+ my $w = sprintf "# Note: CPAN.pm is running in process %d now", pop @rec;
+ my %sleep = (
+ 5 => 30,
+ 6 => 60,
+ 7 => 120,
+ );
+ my $sleep = @rec > 7 ? 300 : ($sleep{scalar @rec}||0);
+ my $verbose = @rec >= 4;
+ while (@rec) {
+ $w .= sprintf " which has been called by process %d", pop @rec;
+ }
+ if ($sleep) {
+ $w .= ".\n\n# Sleeping $sleep seconds to protect other processes\n";
+ }
+ if ($verbose) {
+ warn $w;
+ }
+ local $| = 1;
+ while ($sleep > 0) {
+ printf "\r#%5d", --$sleep;
+ sleep 1;
+ }
+ print "\n";
+}
+$ENV{PERL5_CPAN_IS_RUNNING}=$$;
+$ENV{PERL5_CPANPLUS_IS_RUNNING}=$$; # https://rt.cpan.org/Ticket/Display.html?id=23735
+
+END { $CPAN::End++; &cleanup; }
+
+$CPAN::Signal ||= 0;
+$CPAN::Frontend ||= "CPAN::Shell";
+unless (@CPAN::Defaultsites) {
+ @CPAN::Defaultsites = map {
+ CPAN::URL->new(TEXT => $_, FROM => "DEF")
+ }
+ "http://www.perl.org/CPAN/",
+ "ftp://ftp.perl.org/pub/CPAN/";
+}
+# $CPAN::iCwd (i for initial)
+$CPAN::iCwd ||= CPAN::anycwd();
+$CPAN::Perl ||= CPAN::find_perl();
+$CPAN::Defaultdocs ||= "http://search.cpan.org/perldoc?";
+$CPAN::Defaultrecent ||= "http://search.cpan.org/uploads.rdf";
+$CPAN::Defaultrecent ||= "http://cpan.uwinnipeg.ca/htdocs/cpan.xml";
+
+# our globals are getting a mess
+use vars qw(
+ $AUTOLOAD
+ $Be_Silent
+ $CONFIG_DIRTY
+ $Defaultdocs
+ $Echo_readline
+ $Frontend
+ $GOTOSHELL
+ $HAS_USABLE
+ $Have_warned
+ $MAX_RECURSION
+ $META
+ $RUN_DEGRADED
+ $Signal
+ $SQLite
+ $Suppress_readline
+ $VERSION
+ $autoload_recursion
+ $term
+ @Defaultsites
+ @EXPORT
+ );
+
+$MAX_RECURSION = 32;
+
+@CPAN::ISA = qw(CPAN::Debug Exporter);
+
+# note that these functions live in CPAN::Shell and get executed via
+# AUTOLOAD when called directly
+@EXPORT = qw(
+ autobundle
+ bundle
+ clean
+ cvs_import
+ expand
+ force
+ fforce
+ get
+ install
+ install_tested
+ is_tested
+ make
+ mkmyconfig
+ notest
+ perldoc
+ readme
+ recent
+ recompile
+ report
+ shell
+ smoke
+ test
+ upgrade
+ );
+
+sub soft_chdir_with_alternatives ($);
+
+{
+ $autoload_recursion ||= 0;
+
+ #-> sub CPAN::AUTOLOAD ;
+ sub AUTOLOAD { ## no critic
+ $autoload_recursion++;
+ my($l) = $AUTOLOAD;
+ $l =~ s/.*:://;
+ if ($CPAN::Signal) {
+ warn "Refusing to autoload '$l' while signal pending";
+ $autoload_recursion--;
+ return;
+ }
+ if ($autoload_recursion > 1) {
+ my $fullcommand = join " ", map { "'$_'" } $l, @_;
+ warn "Refusing to autoload $fullcommand in recursion\n";
+ $autoload_recursion--;
+ return;
+ }
+ my(%export);
+ @export{@EXPORT} = '';
+ CPAN::HandleConfig->load unless $CPAN::Config_loaded++;
+ if (exists $export{$l}) {
+ CPAN::Shell->$l(@_);
+ } else {
+ die(qq{Unknown CPAN command "$AUTOLOAD". }.
+ qq{Type ? for help.\n});
+ }
+ $autoload_recursion--;
+ }
+}
+
+{
+ my $x = *SAVEOUT; # avoid warning
+ open($x,">&STDOUT") or die "dup failed";
+ my $redir = 0;
+ sub _redirect(@) {
+ #die if $redir;
+ local $_;
+ push(@_,undef);
+ while(defined($_=shift)) {
+ if (s/^\s*>//){
+ my ($m) = s/^>// ? ">" : "";
+ s/\s+//;
+ $_=shift unless length;
+ die "no dest" unless defined;
+ open(STDOUT,">$m$_") or die "open:$_:$!\n";
+ $redir=1;
+ } elsif ( s/^\s*\|\s*// ) {
+ my $pipe="| $_";
+ while(defined($_[0])){
+ $pipe .= ' ' . shift;
+ }
+ open(STDOUT,$pipe) or die "open:$pipe:$!\n";
+ $redir=1;
+ } else {
+ push(@_,$_);
+ }
+ }
+ return @_;
+ }
+ sub _unredirect {
+ return unless $redir;
+ $redir = 0;
+ ## redirect: unredirect and propagate errors. explicit close to wait for pipe.
+ close(STDOUT);
+ open(STDOUT,">&SAVEOUT");
+ die "$@" if "$@";
+ ## redirect: done
+ }
+}
+
+sub _uniq {
+ my(@list) = @_;
+ my %seen;
+ return grep { !$seen{$_}++ } @list;
+}
+
+#-> sub CPAN::shell ;
+sub shell {
+ my($self) = @_;
+ $Suppress_readline = ! -t STDIN unless defined $Suppress_readline;
+ CPAN::HandleConfig->load unless $CPAN::Config_loaded++;
+
+ my $oprompt = shift || CPAN::Prompt->new;
+ my $prompt = $oprompt;
+ my $commandline = shift || "";
+ $CPAN::CurrentCommandId ||= 1;
+
+ local($^W) = 1;
+ unless ($Suppress_readline) {
+ require Term::ReadLine;
+ if (! $term
+ or
+ $term->ReadLine eq "Term::ReadLine::Stub"
+ ) {
+ $term = Term::ReadLine->new('CPAN Monitor');
+ }
+ if ($term->ReadLine eq "Term::ReadLine::Gnu") {
+ my $attribs = $term->Attribs;
+ $attribs->{attempted_completion_function} = sub {
+ &CPAN::Complete::gnu_cpl;
+ }
+ } else {
+ $readline::rl_completion_function =
+ $readline::rl_completion_function = 'CPAN::Complete::cpl';
+ }
+ if (my $histfile = $CPAN::Config->{'histfile'}) {{
+ unless ($term->can("AddHistory")) {
+ $CPAN::Frontend->mywarn("Terminal does not support AddHistory.\n");
+ last;
+ }
+ $META->readhist($term,$histfile);
+ }}
+ for ($CPAN::Config->{term_ornaments}) { # alias
+ local $Term::ReadLine::termcap_nowarn = 1;
+ $term->ornaments($_) if defined;
+ }
+ # $term->OUT is autoflushed anyway
+ my $odef = select STDERR;
+ $| = 1;
+ select STDOUT;
+ $| = 1;
+ select $odef;
+ }
+
+ $META->checklock();
+ my @cwd = grep { defined $_ and length $_ }
+ CPAN::anycwd(),
+ File::Spec->can("tmpdir") ? File::Spec->tmpdir() : (),
+ File::Spec->rootdir();
+ my $try_detect_readline;
+ $try_detect_readline = $term->ReadLine eq "Term::ReadLine::Stub" if $term;
+ unless ($CPAN::Config->{inhibit_startup_message}) {
+ my $rl_avail = $Suppress_readline ? "suppressed" :
+ ($term->ReadLine ne "Term::ReadLine::Stub") ? "enabled" :
+ "available (maybe install Bundle::CPAN or Bundle::CPANxxl?)";
+ $CPAN::Frontend->myprint(
+ sprintf qq{
+cpan shell -- CPAN exploration and modules installation (v%s)
+Enter 'h' for help.
+
+},
+ $CPAN::VERSION,
+ )
+ }
+ my($continuation) = "";
+ my $last_term_ornaments;
+ SHELLCOMMAND: while () {
+ if ($Suppress_readline) {
+ if ($Echo_readline) {
+ $|=1;
+ }
+ print $prompt;
+ last SHELLCOMMAND unless defined ($_ = <> );
+ if ($Echo_readline) {
+ # backdoor: I could not find a way to record sessions
+ print $_;
+ }
+ chomp;
+ } else {
+ last SHELLCOMMAND unless
+ defined ($_ = $term->readline($prompt, $commandline));
+ }
+ $_ = "$continuation$_" if $continuation;
+ s/^\s+//;
+ next SHELLCOMMAND if /^$/;
+ s/^\s*\?\s*/help /;
+ if (/^(?:q(?:uit)?|bye|exit)\s*$/i) {
+ last SHELLCOMMAND;
+ } elsif (s/\\$//s) {
+ chomp;
+ $continuation = $_;
+ $prompt = " > ";
+ } elsif (/^\!/) {
+ s/^\!//;
+ my($eval) = $_;
+ package
+ CPAN::Eval; # hide from the indexer
+ use strict;
+ use vars qw($import_done);
+ CPAN->import(':DEFAULT') unless $import_done++;
+ CPAN->debug("eval[$eval]") if $CPAN::DEBUG;
+ eval($eval);
+ warn $@ if $@;
+ $continuation = "";
+ $prompt = $oprompt;
+ } elsif (/./) {
+ my(@line);
+ eval { @line = Text::ParseWords::shellwords($_) };
+ warn($@), next SHELLCOMMAND if $@;
+ warn("Text::Parsewords could not parse the line [$_]"),
+ next SHELLCOMMAND unless @line;
+ $CPAN::META->debug("line[".join("|",@line)."]") if $CPAN::DEBUG;
+ my $command = shift @line;
+ eval {
+ local (*STDOUT)=*STDOUT;
+ @line = _redirect(@line);
+ CPAN::Shell->$command(@line)
+ };
+ my $command_error = $@;
+ _unredirect;
+ my $reported_error;
+ if ($command_error) {
+ my $err = $command_error;
+ if (ref $err and $err->isa('CPAN::Exception::blocked_urllist')) {
+ $CPAN::Frontend->mywarn("Client not fully configured, please proceed with configuring.$err");
+ $reported_error = ref $err;
+ } else {
+ # I'd prefer never to arrive here and make all errors exception objects
+ if ($err =~ /\S/) {
+ require Carp;
+ require Dumpvalue;
+ my $dv = Dumpvalue->new(tick => '"');
+ Carp::cluck(sprintf "Catching error: %s", $dv->stringify($err));
+ }
+ }
+ }
+ if ($command =~ /^(
+ # classic commands
+ make
+ |test
+ |install
+ |clean
+
+ # pragmas for classic commands
+ |ff?orce
+ |notest
+
+ # compounds
+ |report
+ |smoke
+ |upgrade
+ )$/x) {
+ # only commands that tell us something about failed distros
+ # eval necessary for people without an urllist
+ eval {CPAN::Shell->failed($CPAN::CurrentCommandId,1);};
+ if (my $err = $@) {
+ unless (ref $err and $reported_error eq ref $err) {
+ die $@;
+ }
+ }
+ }
+ soft_chdir_with_alternatives(\@cwd);
+ $CPAN::Frontend->myprint("\n");
+ $continuation = "";
+ $CPAN::CurrentCommandId++;
+ $prompt = $oprompt;
+ }
+ } continue {
+ $commandline = ""; # I do want to be able to pass a default to
+ # shell, but on the second command I see no
+ # use in that
+ $Signal=0;
+ CPAN::Queue->nullify_queue;
+ if ($try_detect_readline) {
+ if ($CPAN::META->has_inst("Term::ReadLine::Gnu")
+ ||
+ $CPAN::META->has_inst("Term::ReadLine::Perl")
+ ) {
+ delete $INC{"Term/ReadLine.pm"};
+ my $redef = 0;
+ local($SIG{__WARN__}) = CPAN::Shell::paintdots_onreload(\$redef);
+ require Term::ReadLine;
+ $CPAN::Frontend->myprint("\n$redef subroutines in ".
+ "Term::ReadLine redefined\n");
+ $GOTOSHELL = 1;
+ }
+ }
+ if ($term and $term->can("ornaments")) {
+ for ($CPAN::Config->{term_ornaments}) { # alias
+ if (defined $_) {
+ if (not defined $last_term_ornaments
+ or $_ != $last_term_ornaments
+ ) {
+ local $Term::ReadLine::termcap_nowarn = 1;
+ $term->ornaments($_);
+ $last_term_ornaments = $_;
+ }
+ } else {
+ undef $last_term_ornaments;
+ }
+ }
+ }
+ for my $class (qw(Module Distribution)) {
+ # again unsafe meta access?
+ for my $dm (sort keys %{$CPAN::META->{readwrite}{"CPAN::$class"}}) {
+ next unless $CPAN::META->{readwrite}{"CPAN::$class"}{$dm}{incommandcolor};
+ CPAN->debug("BUG: $class '$dm' was in command state, resetting");
+ delete $CPAN::META->{readwrite}{"CPAN::$class"}{$dm}{incommandcolor};
+ }
+ }
+ if ($GOTOSHELL) {
+ $GOTOSHELL = 0; # not too often
+ $META->savehist if $CPAN::term && $CPAN::term->can("GetHistory");
+ @_ = ($oprompt,"");
+ goto &shell;
+ }
+ }
+ soft_chdir_with_alternatives(\@cwd);
+}
+
+#-> CPAN::soft_chdir_with_alternatives ;
+sub soft_chdir_with_alternatives ($) {
+ my($cwd) = @_;
+ unless (@$cwd) {
+ my $root = File::Spec->rootdir();
+ $CPAN::Frontend->mywarn(qq{Warning: no good directory to chdir to!
+Trying '$root' as temporary haven.
+});
+ push @$cwd, $root;
+ }
+ while () {
+ if (chdir $cwd->[0]) {
+ return;
+ } else {
+ if (@$cwd>1) {
+ $CPAN::Frontend->mywarn(qq{Could not chdir to "$cwd->[0]": $!
+Trying to chdir to "$cwd->[1]" instead.
+});
+ shift @$cwd;
+ } else {
+ $CPAN::Frontend->mydie(qq{Could not chdir to "$cwd->[0]": $!});
+ }
+ }
+ }
+}
+
+sub _flock {
+ my($fh,$mode) = @_;
+ if ( $Config::Config{d_flock} || $Config::Config{d_fcntl_can_lock} ) {
+ return flock $fh, $mode;
+ } elsif (!$Have_warned->{"d_flock"}++) {
+ $CPAN::Frontend->mywarn("Your OS does not seem to support locking; continuing and ignoring all locking issues\n");
+ $CPAN::Frontend->mysleep(5);
+ return 1;
+ } else {
+ return 1;
+ }
+}
+
+sub _yaml_module () {
+ my $yaml_module = $CPAN::Config->{yaml_module} || "YAML";
+ if (
+ $yaml_module ne "YAML"
+ &&
+ !$CPAN::META->has_inst($yaml_module)
+ ) {
+ # $CPAN::Frontend->mywarn("'$yaml_module' not installed, falling back to 'YAML'\n");
+ $yaml_module = "YAML";
+ }
+ if ($yaml_module eq "YAML"
+ &&
+ $CPAN::META->has_inst($yaml_module)
+ &&
+ $YAML::VERSION < 0.60
+ &&
+ !$Have_warned->{"YAML"}++
+ ) {
+ $CPAN::Frontend->mywarn("Warning: YAML version '$YAML::VERSION' is too low, please upgrade!\n".
+ "I'll continue but problems are *very* likely to happen.\n"
+ );
+ $CPAN::Frontend->mysleep(5);
+ }
+ return $yaml_module;
+}
+
+# CPAN::_yaml_loadfile
+sub _yaml_loadfile {
+ my($self,$local_file) = @_;
+ return +[] unless -s $local_file;
+ my $yaml_module = _yaml_module;
+ if ($CPAN::META->has_inst($yaml_module)) {
+ # temporarily enable yaml code deserialisation
+ no strict 'refs';
+ # 5.6.2 could not do the local() with the reference
+ # so we do it manually instead
+ my $old_loadcode = ${"$yaml_module\::LoadCode"};
+ ${ "$yaml_module\::LoadCode" } = $CPAN::Config->{yaml_load_code} || 0;
+
+ my ($code, @yaml);
+ if ($code = UNIVERSAL::can($yaml_module, "LoadFile")) {
+ eval { @yaml = $code->($local_file); };
+ if ($@) {
+ # this shall not be done by the frontend
+ die CPAN::Exception::yaml_process_error->new($yaml_module,$local_file,"parse",$@);
+ }
+ } elsif ($code = UNIVERSAL::can($yaml_module, "Load")) {
+ local *FH;
+ unless (open FH, $local_file) {
+ $CPAN::Frontend->mywarn("Could not open '$local_file': $!");
+ return +[];
+ }
+ local $/;
+ my $ystream = <FH>;
+ eval { @yaml = $code->($ystream); };
+ if ($@) {
+ # this shall not be done by the frontend
+ die CPAN::Exception::yaml_process_error->new($yaml_module,$local_file,"parse",$@);
+ }
+ }
+ ${"$yaml_module\::LoadCode"} = $old_loadcode;
+ return \@yaml;
+ } else {
+ # this shall not be done by the frontend
+ die CPAN::Exception::yaml_not_installed->new($yaml_module, $local_file, "parse");
+ }
+ return +[];
+}
+
+# CPAN::_yaml_dumpfile
+sub _yaml_dumpfile {
+ my($self,$local_file,@what) = @_;
+ my $yaml_module = _yaml_module;
+ if ($CPAN::META->has_inst($yaml_module)) {
+ my $code;
+ if (UNIVERSAL::isa($local_file, "FileHandle")) {
+ $code = UNIVERSAL::can($yaml_module, "Dump");
+ eval { print $local_file $code->(@what) };
+ } elsif ($code = UNIVERSAL::can($yaml_module, "DumpFile")) {
+ eval { $code->($local_file,@what); };
+ } elsif ($code = UNIVERSAL::can($yaml_module, "Dump")) {
+ local *FH;
+ open FH, ">$local_file" or die "Could not open '$local_file': $!";
+ print FH $code->(@what);
+ }
+ if ($@) {
+ die CPAN::Exception::yaml_process_error->new($yaml_module,$local_file,"dump",$@);
+ }
+ } else {
+ if (UNIVERSAL::isa($local_file, "FileHandle")) {
+ # I think this case does not justify a warning at all
+ } else {
+ die CPAN::Exception::yaml_not_installed->new($yaml_module, $local_file, "dump");
+ }
+ }
+}
+
+sub _init_sqlite () {
+ unless ($CPAN::META->has_inst("CPAN::SQLite")) {
+ $CPAN::Frontend->mywarn(qq{CPAN::SQLite not installed, trying to work without\n})
+ unless $Have_warned->{"CPAN::SQLite"}++;
+ return;
+ }
+ require CPAN::SQLite::META; # not needed since CVS version of 2006-12-17
+ $CPAN::SQLite ||= CPAN::SQLite::META->new($CPAN::META);
+}
+
+{
+ my $negative_cache = {};
+ sub _sqlite_running {
+ if ($negative_cache->{time} && time < $negative_cache->{time} + 60) {
+ # need to cache the result, otherwise too slow
+ return $negative_cache->{fact};
+ } else {
+ $negative_cache = {}; # reset
+ }
+ my $ret = $CPAN::Config->{use_sqlite} && ($CPAN::SQLite || _init_sqlite());
+ return $ret if $ret; # fast anyway
+ $negative_cache->{time} = time;
+ return $negative_cache->{fact} = $ret;
+ }
+}
+
+$META ||= CPAN->new; # In case we re-eval ourselves we need the ||
+
+# from here on only subs.
+################################################################################
+
+sub _perl_fingerprint {
+ my($self,$other_fingerprint) = @_;
+ my $dll = eval {OS2::DLLname()};
+ my $mtime_dll = 0;
+ if (defined $dll) {
+ $mtime_dll = (-f $dll ? (stat(_))[9] : '-1');
+ }
+ my $mtime_perl = (-f CPAN::find_perl ? (stat(_))[9] : '-1');
+ my $this_fingerprint = {
+ '$^X' => CPAN::find_perl,
+ sitearchexp => $Config::Config{sitearchexp},
+ 'mtime_$^X' => $mtime_perl,
+ 'mtime_dll' => $mtime_dll,
+ };
+ if ($other_fingerprint) {
+ if (exists $other_fingerprint->{'stat($^X)'}) { # repair fp from rev. 1.88_57
+ $other_fingerprint->{'mtime_$^X'} = $other_fingerprint->{'stat($^X)'}[9];
+ }
+ # mandatory keys since 1.88_57
+ for my $key (qw($^X sitearchexp mtime_dll mtime_$^X)) {
+ return unless $other_fingerprint->{$key} eq $this_fingerprint->{$key};
+ }
+ return 1;
+ } else {
+ return $this_fingerprint;
+ }
+}
+
+sub suggest_myconfig () {
+ SUGGEST_MYCONFIG: if(!$INC{'CPAN/MyConfig.pm'}) {
+ $CPAN::Frontend->myprint("You don't seem to have a user ".
+ "configuration (MyConfig.pm) yet.\n");
+ my $new = CPAN::Shell::colorable_makemaker_prompt("Do you want to create a ".
+ "user configuration now? (Y/n)",
+ "yes");
+ if($new =~ m{^y}i) {
+ CPAN::Shell->mkmyconfig();
+ return &checklock;
+ } else {
+ $CPAN::Frontend->mydie("OK, giving up.");
+ }
+ }
+}
+
+#-> sub CPAN::all_objects ;
+sub all_objects {
+ my($mgr,$class) = @_;
+ CPAN::HandleConfig->load unless $CPAN::Config_loaded++;
+ CPAN->debug("mgr[$mgr] class[$class]") if $CPAN::DEBUG;
+ CPAN::Index->reload;
+ values %{ $META->{readwrite}{$class} }; # unsafe meta access, ok
+}
+
+# Called by shell, not in batch mode. In batch mode I see no risk in
+# having many processes updating something as installations are
+# continually checked at runtime. In shell mode I suspect it is
+# unintentional to open more than one shell at a time
+
+#-> sub CPAN::checklock ;
+sub checklock {
+ my($self) = @_;
+ my $lockfile = File::Spec->catfile($CPAN::Config->{cpan_home},".lock");
+ if (-f $lockfile && -M _ > 0) {
+ my $fh = FileHandle->new($lockfile) or
+ $CPAN::Frontend->mydie("Could not open lockfile '$lockfile': $!");
+ my $otherpid = <$fh>;
+ my $otherhost = <$fh>;
+ $fh->close;
+ if (defined $otherpid && length $otherpid) {
+ chomp $otherpid;
+ }
+ if (defined $otherhost && length $otherhost) {
+ chomp $otherhost;
+ }
+ my $thishost = hostname();
+ my $ask_if_degraded_wanted = 0;
+ if (defined $otherhost && defined $thishost &&
+ $otherhost ne '' && $thishost ne '' &&
+ $otherhost ne $thishost) {
+ $CPAN::Frontend->mydie(sprintf("CPAN.pm panic: Lockfile '$lockfile'\n".
+ "reports other host $otherhost and other ".
+ "process $otherpid.\n".
+ "Cannot proceed.\n"));
+ } elsif ($RUN_DEGRADED) {
+ $CPAN::Frontend->mywarn("Running in downgraded mode (experimental)\n");
+ } elsif (defined $otherpid && $otherpid) {
+ return if $$ == $otherpid; # should never happen
+ $CPAN::Frontend->mywarn(
+ qq{
+There seems to be running another CPAN process (pid $otherpid). Contacting...
+});
+ if (kill 0, $otherpid or $!{EPERM}) {
+ $CPAN::Frontend->mywarn(qq{Other job is running.\n});
+ $ask_if_degraded_wanted = 1;
+ } elsif (-w $lockfile) {
+ my($ans) =
+ CPAN::Shell::colorable_makemaker_prompt
+ (qq{Other job not responding. Shall I overwrite }.
+ qq{the lockfile '$lockfile'? (Y/n)},"y");
+ $CPAN::Frontend->myexit("Ok, bye\n")
+ unless $ans =~ /^y/i;
+ } else {
+ Carp::croak(
+ qq{Lockfile '$lockfile' not writable by you. }.
+ qq{Cannot proceed.\n}.
+ qq{ On UNIX try:\n}.
+ qq{ rm '$lockfile'\n}.
+ qq{ and then rerun us.\n}
+ );
+ }
+ } elsif ($^O eq "MSWin32") {
+ $CPAN::Frontend->mywarn(
+ qq{
+There seems to be running another CPAN process according to '$lockfile'.
+});
+ $ask_if_degraded_wanted = 1;
+ } else {
+ $CPAN::Frontend->mydie(sprintf("CPAN.pm panic: Found invalid lockfile ".
+ "'$lockfile', please remove. Cannot proceed.\n"));
+ }
+ if ($ask_if_degraded_wanted) {
+ my($ans) =
+ CPAN::Shell::colorable_makemaker_prompt
+ (qq{Shall I try to run in downgraded }.
+ qq{mode? (Y/n)},"y");
+ if ($ans =~ /^y/i) {
+ $CPAN::Frontend->mywarn("Running in downgraded mode (experimental).
+Please report if something unexpected happens\n");
+ $RUN_DEGRADED = 1;
+ for ($CPAN::Config) {
+ # XXX
+ # $_->{build_dir_reuse} = 0; # 2006-11-17 akoenig Why was that?
+ $_->{commandnumber_in_prompt} = 0; # visibility
+ $_->{histfile} = ""; # who should win otherwise?
+ $_->{cache_metadata} = 0; # better would be a lock?
+ $_->{use_sqlite} = 0; # better would be a write lock!
+ $_->{auto_commit} = 0; # we are violent, do not persist
+ $_->{test_report} = 0; # Oliver Paukstadt had sent wrong reports in degraded mode
+ }
+ } else {
+ my $msg = "You may want to kill the other job and delete the lockfile.";
+ if (defined $otherpid) {
+ $msg .= " Something like:
+ kill $otherpid
+ rm $lockfile
+";
+ }
+ $CPAN::Frontend->mydie("\n$msg");
+ }
+ }
+ }
+ my $dotcpan = $CPAN::Config->{cpan_home};
+ eval { File::Path::mkpath($dotcpan);};
+ if ($@) {
+ # A special case at least for Jarkko.
+ my $firsterror = $@;
+ my $seconderror;
+ my $symlinkcpan;
+ if (-l $dotcpan) {
+ $symlinkcpan = readlink $dotcpan;
+ die "readlink $dotcpan failed: $!" unless defined $symlinkcpan;
+ eval { File::Path::mkpath($symlinkcpan); };
+ if ($@) {
+ $seconderror = $@;
+ } else {
+ $CPAN::Frontend->mywarn(qq{
+Working directory $symlinkcpan created.
+});
+ }
+ }
+ unless (-d $dotcpan) {
+ my $mess = qq{
+Your configuration suggests "$dotcpan" as your
+CPAN.pm working directory. I could not create this directory due
+to this error: $firsterror\n};
+ $mess .= qq{
+As "$dotcpan" is a symlink to "$symlinkcpan",
+I tried to create that, but I failed with this error: $seconderror
+} if $seconderror;
+ $mess .= qq{
+Please make sure the directory exists and is writable.
+};
+ $CPAN::Frontend->mywarn($mess);
+ return suggest_myconfig;
+ }
+ } # $@ after eval mkpath $dotcpan
+ if (0) { # to test what happens when a race condition occurs
+ for (reverse 1..10) {
+ print $_, "\n";
+ sleep 1;
+ }
+ }
+ # locking
+ if (!$RUN_DEGRADED && !$self->{LOCKFH}) {
+ my $fh;
+ unless ($fh = FileHandle->new("+>>$lockfile")) {
+ $CPAN::Frontend->mywarn(qq{
+
+Your configuration suggests that CPAN.pm should use a working
+directory of
+ $CPAN::Config->{cpan_home}
+Unfortunately we could not create the lock file
+ $lockfile
+due to '$!'.
+
+Please make sure that the configuration variable
+ \$CPAN::Config->{cpan_home}
+points to a directory where you can write a .lock file. You can set
+this variable in either a CPAN/MyConfig.pm or a CPAN/Config.pm in your
+\@INC path;
+});
+ return suggest_myconfig;
+ }
+ my $sleep = 1;
+ while (!CPAN::_flock($fh, LOCK_EX|LOCK_NB)) {
+ my $err = $! || "unknown error";
+ if ($sleep>3) {
+ $CPAN::Frontend->mydie("Could not lock '$lockfile' with flock: $err; giving up\n");
+ }
+ $CPAN::Frontend->mysleep($sleep+=0.1);
+ $CPAN::Frontend->mywarn("Could not lock '$lockfile' with flock: $err; retrying\n");
+ }
+
+ seek $fh, 0, 0;
+ truncate $fh, 0;
+ $fh->autoflush(1);
+ $fh->print($$, "\n");
+ $fh->print(hostname(), "\n");
+ $self->{LOCK} = $lockfile;
+ $self->{LOCKFH} = $fh;
+ }
+ $SIG{TERM} = sub {
+ my $sig = shift;
+ &cleanup;
+ $CPAN::Frontend->mydie("Got SIG$sig, leaving");
+ };
+ $SIG{INT} = sub {
+ # no blocks!!!
+ my $sig = shift;
+ &cleanup if $Signal;
+ die "Got yet another signal" if $Signal > 1;
+ $CPAN::Frontend->mydie("Got another SIG$sig") if $Signal;
+ $CPAN::Frontend->mywarn("Caught SIG$sig, trying to continue\n");
+ $Signal++;
+ };
+
+# From: Larry Wall <larry@wall.org>
+# Subject: Re: deprecating SIGDIE
+# To: perl5-porters@perl.org
+# Date: Thu, 30 Sep 1999 14:58:40 -0700 (PDT)
+#
+# The original intent of __DIE__ was only to allow you to substitute one
+# kind of death for another on an application-wide basis without respect
+# to whether you were in an eval or not. As a global backstop, it should
+# not be used any more lightly (or any more heavily :-) than class
+# UNIVERSAL. Any attempt to build a general exception model on it should
+# be politely squashed. Any bug that causes every eval {} to have to be
+# modified should be not so politely squashed.
+#
+# Those are my current opinions. It is also my opinion that polite
+# arguments degenerate to personal arguments far too frequently, and that
+# when they do, it's because both people wanted it to, or at least didn't
+# sufficiently want it not to.
+#
+# Larry
+
+ # global backstop to cleanup if we should really die
+ $SIG{__DIE__} = \&cleanup;
+ $self->debug("Signal handler set.") if $CPAN::DEBUG;
+}
+
+#-> sub CPAN::DESTROY ;
+sub DESTROY {
+ &cleanup; # need an eval?
+}
+
+#-> sub CPAN::anycwd ;
+sub anycwd () {
+ my $getcwd;
+ $getcwd = $CPAN::Config->{'getcwd'} || 'cwd';
+ CPAN->$getcwd();
+}
+
+#-> sub CPAN::cwd ;
+sub cwd {Cwd::cwd();}
+
+#-> sub CPAN::getcwd ;
+sub getcwd {Cwd::getcwd();}
+
+#-> sub CPAN::fastcwd ;
+sub fastcwd {Cwd::fastcwd();}
+
+#-> sub CPAN::getdcwd ;
+sub getdcwd {Cwd::getdcwd();}
+
+#-> sub CPAN::backtickcwd ;
+sub backtickcwd {my $cwd = `cwd`; chomp $cwd; $cwd}
+
+# Adapted from Probe::Perl
+#-> sub CPAN::_perl_is_same
+sub _perl_is_same {
+ my ($perl) = @_;
+ return MM->maybe_command($perl)
+ && `$perl -MConfig=myconfig -e print -e myconfig` eq Config->myconfig;
+}
+
+# Adapted in part from Probe::Perl
+#-> sub CPAN::find_perl ;
+sub find_perl () {
+ if ( File::Spec->file_name_is_absolute($^X) ) {
+ return $^X;
+ }
+ else {
+ my $exe = $Config::Config{exe_ext};
+ my @candidates = (
+ File::Spec->catfile($CPAN::iCwd,$^X),
+ $Config::Config{'perlpath'},
+ );
+ for my $perl_name ($^X, 'perl', 'perl5', "perl$]") {
+ for my $path (File::Spec->path(), $Config::Config{'binexp'}) {
+ if ( defined($path) && length $path && -d $path ) {
+ my $perl = File::Spec->catfile($path,$perl_name);
+ push @candidates, $perl;
+ # try with extension if not provided already
+ if ($^O eq 'VMS') {
+ # VMS might have a file version at the end
+ push @candidates, $perl . $exe
+ unless $perl =~ m/$exe(;\d+)?$/i;
+ } elsif (defined $exe && length $exe) {
+ push @candidates, $perl . $exe
+ unless $perl =~ m/$exe$/i;
+ }
+ }
+ }
+ }
+ for my $perl ( @candidates ) {
+ if (MM->maybe_command($perl) && _perl_is_same($perl)) {
+ $^X = $perl;
+ return $perl;
+ }
+ }
+ }
+ return $^X; # default fall back
+}
+
+#-> sub CPAN::exists ;
+sub exists {
+ my($mgr,$class,$id) = @_;
+ CPAN::HandleConfig->load unless $CPAN::Config_loaded++;
+ CPAN::Index->reload;
+ ### Carp::croak "exists called without class argument" unless $class;
+ $id ||= "";
+ $id =~ s/:+/::/g if $class eq "CPAN::Module";
+ my $exists;
+ if (CPAN::_sqlite_running) {
+ $exists = (exists $META->{readonly}{$class}{$id} or
+ $CPAN::SQLite->set($class, $id));
+ } else {
+ $exists = exists $META->{readonly}{$class}{$id};
+ }
+ $exists ||= exists $META->{readwrite}{$class}{$id}; # unsafe meta access, ok
+}
+
+#-> sub CPAN::delete ;
+sub delete {
+ my($mgr,$class,$id) = @_;
+ delete $META->{readonly}{$class}{$id}; # unsafe meta access, ok
+ delete $META->{readwrite}{$class}{$id}; # unsafe meta access, ok
+}
+
+#-> sub CPAN::has_usable
+# has_inst is sometimes too optimistic, we should replace it with this
+# has_usable whenever a case is given
+sub has_usable {
+ my($self,$mod,$message) = @_;
+ return 1 if $HAS_USABLE->{$mod};
+ my $has_inst = $self->has_inst($mod,$message);
+ return unless $has_inst;
+ my $usable;
+ $usable = {
+
+ #
+ # these subroutines die if they believe the installed version is unusable;
+ #
+ 'CPAN::Meta' => [
+ sub {
+ require CPAN::Meta;
+ unless (CPAN::Version->vge(CPAN::Meta->VERSION, 2.110350)) {
+ for ("Will not use CPAN::Meta, need version 2.110350\n") {
+ $CPAN::Frontend->mywarn($_);
+ die $_;
+ }
+ }
+ },
+ ],
+
+ 'CPAN::Meta::Requirements' => [
+ sub {
+ if (defined $CPAN::Meta::Requirements::VERSION
+ && CPAN::Version->vlt($CPAN::Meta::Requirements::VERSION, "2.120920")
+ ) {
+ delete $INC{"CPAN/Meta/Requirements.pm"};
+ }
+ require CPAN::Meta::Requirements;
+ unless (CPAN::Version->vge(CPAN::Meta::Requirements->VERSION, 2.120920)) {
+ for ("Will not use CPAN::Meta::Requirements, need version 2.120920\n") {
+ $CPAN::Frontend->mywarn($_);
+ die $_;
+ }
+ }
+ },
+ ],
+
+ LWP => [ # we frequently had "Can't locate object
+ # method "new" via package "LWP::UserAgent" at
+ # (eval 69) line 2006
+ sub {require LWP},
+ sub {require LWP::UserAgent},
+ sub {require HTTP::Request},
+ sub {require URI::URL;
+ unless (CPAN::Version->vge(URI::URL::->VERSION,0.08)) {
+ for ("Will not use URI::URL, need 0.08\n") {
+ $CPAN::Frontend->mywarn($_);
+ die $_;
+ }
+ }
+ },
+ ],
+ 'Net::FTP' => [
+ sub {
+ my $var = $CPAN::Config->{ftp_proxy} || $ENV{ftp_proxy};
+ if ($var and $var =~ /^http:/i) {
+ # rt #110833
+ for ("Net::FTP cannot handle http proxy") {
+ $CPAN::Frontend->mywarn($_);
+ die $_;
+ }
+ }
+ },
+ sub {require Net::FTP},
+ sub {require Net::Config},
+ ],
+ 'HTTP::Tiny' => [
+ sub {
+ require HTTP::Tiny;
+ unless (CPAN::Version->vge(HTTP::Tiny->VERSION, 0.005)) {
+ for ("Will not use HTTP::Tiny, need version 0.005\n") {
+ $CPAN::Frontend->mywarn($_);
+ die $_;
+ }
+ }
+ },
+ ],
+ 'File::HomeDir' => [
+ sub {require File::HomeDir;
+ unless (CPAN::Version->vge(File::HomeDir::->VERSION, 0.52)) {
+ for ("Will not use File::HomeDir, need 0.52\n") {
+ $CPAN::Frontend->mywarn($_);
+ die $_;
+ }
+ }
+ },
+ ],
+ 'Archive::Tar' => [
+ sub {require Archive::Tar;
+ my $demand = "1.50";
+ unless (CPAN::Version->vge(Archive::Tar::->VERSION, $demand)) {
+ my $atv = Archive::Tar->VERSION;
+ for ("You have Archive::Tar $atv, but $demand or later is recommended. Please upgrade.\n") {
+ $CPAN::Frontend->mywarn($_);
+ # don't die, because we may need
+ # Archive::Tar to upgrade
+ }
+
+ }
+ },
+ ],
+ 'File::Temp' => [
+ # XXX we should probably delete from
+ # %INC too so we can load after we
+ # installed a new enough version --
+ # I'm not sure.
+ sub {require File::Temp;
+ unless (CPAN::Version->vge(File::Temp::->VERSION,0.16)) {
+ for ("Will not use File::Temp, need 0.16\n") {
+ $CPAN::Frontend->mywarn($_);
+ die $_;
+ }
+ }
+ },
+ ]
+ };
+ if ($usable->{$mod}) {
+ local @INC = @INC;
+ pop @INC if $INC[-1] eq '.';
+ for my $c (0..$#{$usable->{$mod}}) {
+ my $code = $usable->{$mod}[$c];
+ my $ret = eval { &$code() };
+ $ret = "" unless defined $ret;
+ if ($@) {
+ # warn "DEBUG: c[$c]\$\@[$@]ret[$ret]";
+ return;
+ }
+ }
+ }
+ return $HAS_USABLE->{$mod} = 1;
+}
+
+sub frontend {
+ shift;
+ $CPAN::Frontend = shift if @_;
+ $CPAN::Frontend;
+}
+
+sub use_inst {
+ my ($self, $module) = @_;
+
+ unless ($self->has_inst($module)) {
+ $self->frontend->mydie("$module not installed, cannot continue");
+ }
+}
+
+#-> sub CPAN::has_inst
+sub has_inst {
+ my($self,$mod,$message) = @_;
+ Carp::croak("CPAN->has_inst() called without an argument")
+ unless defined $mod;
+ my %dont = map { $_ => 1 } keys %{$CPAN::META->{dontload_hash}||{}},
+ keys %{$CPAN::Config->{dontload_hash}||{}},
+ @{$CPAN::Config->{dontload_list}||[]};
+ if (defined $message && $message eq "no" # as far as I remember only used by Nox
+ ||
+ $dont{$mod}
+ ) {
+ $CPAN::META->{dontload_hash}{$mod}||=1; # unsafe meta access, ok
+ return 0;
+ }
+ local @INC = @INC;
+ pop @INC if $INC[-1] eq '.';
+ my $file = $mod;
+ my $obj;
+ $file =~ s|::|/|g;
+ $file .= ".pm";
+ if ($INC{$file}) {
+ # checking %INC is wrong, because $INC{LWP} may be true
+ # although $INC{"URI/URL.pm"} may have failed. But as
+ # I really want to say "blah loaded OK", I have to somehow
+ # cache results.
+ ### warn "$file in %INC"; #debug
+ return 1;
+ } elsif (eval { require $file }) {
+ # eval is good: if we haven't yet read the database it's
+ # perfect and if we have installed the module in the meantime,
+ # it tries again. The second require is only a NOOP returning
+ # 1 if we had success, otherwise it's retrying
+
+ my $mtime = (stat $INC{$file})[9];
+ # privileged files loaded by has_inst; Note: we use $mtime
+ # as a proxy for a checksum.
+ $CPAN::Shell::reload->{$file} = $mtime;
+ my $v = eval "\$$mod\::VERSION";
+ $v = $v ? " (v$v)" : "";
+ CPAN::Shell->optprint("load_module","CPAN: $mod loaded ok$v\n");
+ if ($mod eq "CPAN::WAIT") {
+ push @CPAN::Shell::ISA, 'CPAN::WAIT';
+ }
+ return 1;
+ } elsif ($mod eq "Net::FTP") {
+ $CPAN::Frontend->mywarn(qq{
+ Please, install Net::FTP as soon as possible. CPAN.pm installs it for you
+ if you just type
+ install Bundle::libnet
+
+}) unless $Have_warned->{"Net::FTP"}++;
+ $CPAN::Frontend->mysleep(3);
+ } elsif ($mod eq "Digest::SHA") {
+ if ($Have_warned->{"Digest::SHA"}++) {
+ $CPAN::Frontend->mywarn(qq{CPAN: checksum security checks disabled }.
+ qq{because Digest::SHA not installed.\n});
+ } else {
+ $CPAN::Frontend->mywarn(qq{
+ CPAN: checksum security checks disabled because Digest::SHA not installed.
+ Please consider installing the Digest::SHA module.
+
+});
+ $CPAN::Frontend->mysleep(2);
+ }
+ } elsif ($mod eq "Module::Signature") {
+ # NOT prefs_lookup, we are not a distro
+ my $check_sigs = $CPAN::Config->{check_sigs};
+ if (not $check_sigs) {
+ # they do not want us:-(
+ } elsif (not $Have_warned->{"Module::Signature"}++) {
+ # No point in complaining unless the user can
+ # reasonably install and use it.
+ if (eval { require Crypt::OpenPGP; 1 } ||
+ (
+ defined $CPAN::Config->{'gpg'}
+ &&
+ $CPAN::Config->{'gpg'} =~ /\S/
+ )
+ ) {
+ $CPAN::Frontend->mywarn(qq{
+ CPAN: Module::Signature security checks disabled because Module::Signature
+ not installed. Please consider installing the Module::Signature module.
+ You may also need to be able to connect over the Internet to the public
+ key servers like pool.sks-keyservers.net or pgp.mit.edu.
+
+});
+ $CPAN::Frontend->mysleep(2);
+ }
+ }
+ } else {
+ delete $INC{$file}; # if it inc'd LWP but failed during, say, URI
+ }
+ return 0;
+}
+
+#-> sub CPAN::instance ;
+sub instance {
+ my($mgr,$class,$id) = @_;
+ CPAN::Index->reload;
+ $id ||= "";
+ # unsafe meta access, ok?
+ return $META->{readwrite}{$class}{$id} if exists $META->{readwrite}{$class}{$id};
+ $META->{readwrite}{$class}{$id} ||= $class->new(ID => $id);
+}
+
+#-> sub CPAN::new ;
+sub new {
+ bless {}, shift;
+}
+
+#-> sub CPAN::_exit_messages ;
+sub _exit_messages {
+ my ($self) = @_;
+ $self->{exit_messages} ||= [];
+}
+
+#-> sub CPAN::cleanup ;
+sub cleanup {
+ # warn "cleanup called with arg[@_] End[$CPAN::End] Signal[$Signal]";
+ local $SIG{__DIE__} = '';
+ my($message) = @_;
+ my $i = 0;
+ my $ineval = 0;
+ my($subroutine);
+ while ((undef,undef,undef,$subroutine) = caller(++$i)) {
+ $ineval = 1, last if
+ $subroutine eq '(eval)';
+ }
+ return if $ineval && !$CPAN::End;
+ return unless defined $META->{LOCK};
+ return unless -f $META->{LOCK};
+ $META->savehist;
+ $META->{cachemgr} ||= CPAN::CacheMgr->new('atexit');
+ close $META->{LOCKFH};
+ unlink $META->{LOCK};
+ # require Carp;
+ # Carp::cluck("DEBUGGING");
+ if ( $CPAN::CONFIG_DIRTY ) {
+ $CPAN::Frontend->mywarn("Warning: Configuration not saved.\n");
+ }
+ $CPAN::Frontend->myprint("Lockfile removed.\n");
+ for my $msg ( @{ $META->_exit_messages } ) {
+ $CPAN::Frontend->myprint($msg);
+ }
+}
+
+#-> sub CPAN::readhist
+sub readhist {
+ my($self,$term,$histfile) = @_;
+ my $histsize = $CPAN::Config->{'histsize'} || 100;
+ $term->Attribs->{'MaxHistorySize'} = $histsize if (defined($term->Attribs->{'MaxHistorySize'}));
+ my($fh) = FileHandle->new;
+ open $fh, "<$histfile" or return;
+ local $/ = "\n";
+ while (<$fh>) {
+ chomp;
+ $term->AddHistory($_);
+ }
+ close $fh;
+}
+
+#-> sub CPAN::savehist
+sub savehist {
+ my($self) = @_;
+ my($histfile,$histsize);
+ unless ($histfile = $CPAN::Config->{'histfile'}) {
+ $CPAN::Frontend->mywarn("No history written (no histfile specified).\n");
+ return;
+ }
+ $histsize = $CPAN::Config->{'histsize'} || 100;
+ if ($CPAN::term) {
+ unless ($CPAN::term->can("GetHistory")) {
+ $CPAN::Frontend->mywarn("Terminal does not support GetHistory.\n");
+ return;
+ }
+ } else {
+ return;
+ }
+ my @h = $CPAN::term->GetHistory;
+ splice @h, 0, @h-$histsize if @h>$histsize;
+ my($fh) = FileHandle->new;
+ open $fh, ">$histfile" or $CPAN::Frontend->mydie("Couldn't open >$histfile: $!");
+ local $\ = local $, = "\n";
+ print $fh @h;
+ close $fh;
+}
+
+#-> sub CPAN::is_tested
+sub is_tested {
+ my($self,$what,$when) = @_;
+ unless ($what) {
+ Carp::cluck("DEBUG: empty what");
+ return;
+ }
+ $self->{is_tested}{$what} = $when;
+}
+
+#-> sub CPAN::reset_tested
+# forget all distributions tested -- resets what gets included in PERL5LIB
+sub reset_tested {
+ my ($self) = @_;
+ $self->{is_tested} = {};
+}
+
+#-> sub CPAN::is_installed
+# unsets the is_tested flag: as soon as the thing is installed, it is
+# not needed in set_perl5lib anymore
+sub is_installed {
+ my($self,$what) = @_;
+ delete $self->{is_tested}{$what};
+}
+
+sub _list_sorted_descending_is_tested {
+ my($self) = @_;
+ my $foul = 0;
+ my @sorted = sort
+ { ($self->{is_tested}{$b}||0) <=> ($self->{is_tested}{$a}||0) }
+ grep
+ { if ($foul){ 0 } elsif (-e) { 1 } else { $foul = $_; 0 } }
+ keys %{$self->{is_tested}};
+ if ($foul) {
+ $CPAN::Frontend->mywarn("Lost build_dir detected ($foul), giving up all cached test results of currently running session.\n");
+ for my $dbd (sort keys %{$self->{is_tested}}) { # distro-build-dir
+ SEARCH: for my $d (sort { $a->id cmp $b->id } $CPAN::META->all_objects("CPAN::Distribution")) {
+ if ($d->{build_dir} && $d->{build_dir} eq $dbd) {
+ $CPAN::Frontend->mywarn(sprintf "Flushing cache for %s\n", $d->pretty_id);
+ $d->fforce("");
+ last SEARCH;
+ }
+ }
+ delete $self->{is_tested}{$dbd};
+ }
+ return ();
+ } else {
+ return @sorted;
+ }
+}
+
+#-> sub CPAN::set_perl5lib
+# Notes on max environment variable length:
+# - Win32 : XP or later, 8191; Win2000 or NT4, 2047
+{
+my $fh;
+sub set_perl5lib {
+ my($self,$for) = @_;
+ unless ($for) {
+ (undef,undef,undef,$for) = caller(1);
+ $for =~ s/.*://;
+ }
+ $self->{is_tested} ||= {};
+ return unless %{$self->{is_tested}};
+ my $env = $ENV{PERL5LIB};
+ $env = $ENV{PERLLIB} unless defined $env;
+ my @env;
+ push @env, split /\Q$Config::Config{path_sep}\E/, $env if defined $env and length $env;
+ #my @dirs = map {("$_/blib/arch", "$_/blib/lib")} keys %{$self->{is_tested}};
+ #$CPAN::Frontend->myprint("Prepending @dirs to PERL5LIB.\n");
+
+ my @dirs = map {("$_/blib/arch", "$_/blib/lib")} $self->_list_sorted_descending_is_tested;
+ return if !@dirs;
+
+ if (@dirs < 12) {
+ $CPAN::Frontend->optprint('perl5lib', "Prepending @dirs to PERL5LIB for '$for'\n");
+ $ENV{PERL5LIB} = join $Config::Config{path_sep}, @dirs, @env;
+ } elsif (@dirs < 24 ) {
+ my @d = map {my $cp = $_;
+ $cp =~ s/^\Q$CPAN::Config->{build_dir}\E/%BUILDDIR%/;
+ $cp
+ } @dirs;
+ $CPAN::Frontend->optprint('perl5lib', "Prepending @d to PERL5LIB; ".
+ "%BUILDDIR%=$CPAN::Config->{build_dir} ".
+ "for '$for'\n"
+ );
+ $ENV{PERL5LIB} = join $Config::Config{path_sep}, @dirs, @env;
+ } else {
+ my $cnt = keys %{$self->{is_tested}};
+ $CPAN::Frontend->optprint('perl5lib', "Prepending blib/arch and blib/lib of ".
+ "$cnt build dirs to PERL5LIB; ".
+ "for '$for'\n"
+ );
+ $ENV{PERL5LIB} = join $Config::Config{path_sep}, @dirs, @env;
+ }
+}}
+
+
+1;
+
+
+__END__
+
+=head1 NAME
+
+CPAN - query, download and build perl modules from CPAN sites
+
+=head1 SYNOPSIS
+
+Interactive mode:
+
+ perl -MCPAN -e shell
+
+--or--
+
+ cpan
+
+Basic commands:
+
+ # Modules:
+
+ cpan> install Acme::Meta # in the shell
+
+ CPAN::Shell->install("Acme::Meta"); # in perl
+
+ # Distributions:
+
+ cpan> install NWCLARK/Acme-Meta-0.02.tar.gz # in the shell
+
+ CPAN::Shell->
+ install("NWCLARK/Acme-Meta-0.02.tar.gz"); # in perl
+
+ # module objects:
+
+ $mo = CPAN::Shell->expandany($mod);
+ $mo = CPAN::Shell->expand("Module",$mod); # same thing
+
+ # distribution objects:
+
+ $do = CPAN::Shell->expand("Module",$mod)->distribution;
+ $do = CPAN::Shell->expandany($distro); # same thing
+ $do = CPAN::Shell->expand("Distribution",
+ $distro); # same thing
+
+=head1 DESCRIPTION
+
+The CPAN module automates or at least simplifies the make and install
+of perl modules and extensions. It includes some primitive searching
+capabilities and knows how to use LWP, HTTP::Tiny, Net::FTP and certain
+external download clients to fetch distributions from the net.
+
+These are fetched from one or more mirrored CPAN (Comprehensive
+Perl Archive Network) sites and unpacked in a dedicated directory.
+
+The CPAN module also supports named and versioned
+I<bundles> of modules. Bundles simplify handling of sets of
+related modules. See Bundles below.
+
+The package contains a session manager and a cache manager. The
+session manager keeps track of what has been fetched, built, and
+installed in the current session. The cache manager keeps track of the
+disk space occupied by the make processes and deletes excess space
+using a simple FIFO mechanism.
+
+All methods provided are accessible in a programmer style and in an
+interactive shell style.
+
+=head2 CPAN::shell([$prompt, $command]) Starting Interactive Mode
+
+Enter interactive mode by running
+
+ perl -MCPAN -e shell
+
+or
+
+ cpan
+
+which puts you into a readline interface. If C<Term::ReadKey> and
+either of C<Term::ReadLine::Perl> or C<Term::ReadLine::Gnu> are installed,
+history and command completion are supported.
+
+Once at the command line, type C<h> for one-page help
+screen; the rest should be self-explanatory.
+
+The function call C<shell> takes two optional arguments: one the
+prompt, the second the default initial command line (the latter
+only works if a real ReadLine interface module is installed).
+
+The most common uses of the interactive modes are
+
+=over 2
+
+=item Searching for authors, bundles, distribution files and modules
+
+There are corresponding one-letter commands C<a>, C<b>, C<d>, and C<m>
+for each of the four categories and another, C<i> for any of the
+mentioned four. Each of the four entities is implemented as a class
+with slightly differing methods for displaying an object.
+
+Arguments to these commands are either strings exactly matching
+the identification string of an object, or regular expressions
+matched case-insensitively against various attributes of the
+objects. The parser only recognizes a regular expression when you
+enclose it with slashes.
+
+The principle is that the number of objects found influences how an
+item is displayed. If the search finds one item, the result is
+displayed with the rather verbose method C<as_string>, but if
+more than one is found, each object is displayed with the terse method
+C<as_glimpse>.
+
+Examples:
+
+ cpan> m Acme::MetaSyntactic
+ Module id = Acme::MetaSyntactic
+ CPAN_USERID BOOK (Philippe Bruhat (BooK) <[...]>)
+ CPAN_VERSION 0.99
+ CPAN_FILE B/BO/BOOK/Acme-MetaSyntactic-0.99.tar.gz
+ UPLOAD_DATE 2006-11-06
+ MANPAGE Acme::MetaSyntactic - Themed metasyntactic variables names
+ INST_FILE /usr/local/lib/perl/5.10.0/Acme/MetaSyntactic.pm
+ INST_VERSION 0.99
+ cpan> a BOOK
+ Author id = BOOK
+ EMAIL [...]
+ FULLNAME Philippe Bruhat (BooK)
+ cpan> d BOOK/Acme-MetaSyntactic-0.99.tar.gz
+ Distribution id = B/BO/BOOK/Acme-MetaSyntactic-0.99.tar.gz
+ CPAN_USERID BOOK (Philippe Bruhat (BooK) <[...]>)
+ CONTAINSMODS Acme::MetaSyntactic Acme::MetaSyntactic::Alias [...]
+ UPLOAD_DATE 2006-11-06
+ cpan> m /lorem/
+ Module = Acme::MetaSyntactic::loremipsum (BOOK/Acme-MetaSyntactic-0.99.tar.gz)
+ Module Text::Lorem (ADEOLA/Text-Lorem-0.3.tar.gz)
+ Module Text::Lorem::More (RKRIMEN/Text-Lorem-More-0.12.tar.gz)
+ Module Text::Lorem::More::Source (RKRIMEN/Text-Lorem-More-0.12.tar.gz)
+ cpan> i /berlin/
+ Distribution BEATNIK/Filter-NumberLines-0.02.tar.gz
+ Module = DateTime::TimeZone::Europe::Berlin (DROLSKY/DateTime-TimeZone-0.7904.tar.gz)
+ Module Filter::NumberLines (BEATNIK/Filter-NumberLines-0.02.tar.gz)
+ Author [...]
+
+The examples illustrate several aspects: the first three queries
+target modules, authors, or distros directly and yield exactly one
+result. The last two use regular expressions and yield several
+results. The last one targets all of bundles, modules, authors, and
+distros simultaneously. When more than one result is available, they
+are printed in one-line format.
+
+=item C<get>, C<make>, C<test>, C<install>, C<clean> modules or distributions
+
+These commands take any number of arguments and investigate what is
+necessary to perform the action. Argument processing is as follows:
+
+ known module name in format Foo/Bar.pm module
+ other embedded slash distribution
+ - with trailing slash dot directory
+ enclosing slashes regexp
+ known module name in format Foo::Bar module
+
+If the argument is a distribution file name (recognized by embedded
+slashes), it is processed. If it is a module, CPAN determines the
+distribution file in which this module is included and processes that,
+following any dependencies named in the module's META.yml or
+Makefile.PL (this behavior is controlled by the configuration
+parameter C<prerequisites_policy>). If an argument is enclosed in
+slashes it is treated as a regular expression: it is expanded and if
+the result is a single object (distribution, bundle or module), this
+object is processed.
+
+Example:
+
+ install Dummy::Perl # installs the module
+ install AUXXX/Dummy-Perl-3.14.tar.gz # installs that distribution
+ install /Dummy-Perl-3.14/ # same if the regexp is unambiguous
+
+C<get> downloads a distribution file and untars or unzips it, C<make>
+builds it, C<test> runs the test suite, and C<install> installs it.
+
+Any C<make> or C<test> is run unconditionally. An
+
+ install <distribution_file>
+
+is also run unconditionally. But for
+
+ install <module>
+
+CPAN checks whether an install is needed and prints
+I<module up to date> if the distribution file containing
+the module doesn't need updating.
+
+CPAN also keeps track of what it has done within the current session
+and doesn't try to build a package a second time regardless of whether it
+succeeded or not. It does not repeat a test run if the test
+has been run successfully before. Same for install runs.
+
+The C<force> pragma may precede another command (currently: C<get>,
+C<make>, C<test>, or C<install>) to execute the command from scratch
+and attempt to continue past certain errors. See the section below on
+the C<force> and the C<fforce> pragma.
+
+The C<notest> pragma skips the test part in the build
+process.
+
+Example:
+
+ cpan> notest install Tk
+
+A C<clean> command results in a
+
+ make clean
+
+being executed within the distribution file's working directory.
+
+=item C<readme>, C<perldoc>, C<look> module or distribution
+
+C<readme> displays the README file of the associated distribution.
+C<Look> gets and untars (if not yet done) the distribution file,
+changes to the appropriate directory and opens a subshell process in
+that directory. C<perldoc> displays the module's pod documentation
+in html or plain text format.
+
+=item C<ls> author
+
+=item C<ls> globbing_expression
+
+The first form lists all distribution files in and below an author's
+CPAN directory as stored in the CHECKSUMS files distributed on
+CPAN. The listing recurses into subdirectories.
+
+The second form limits or expands the output with shell
+globbing as in the following examples:
+
+ ls JV/make*
+ ls GSAR/*make*
+ ls */*make*
+
+The last example is very slow and outputs extra progress indicators
+that break the alignment of the result.
+
+Note that globbing only lists directories explicitly asked for, for
+example FOO/* will not list FOO/bar/Acme-Sthg-n.nn.tar.gz. This may be
+regarded as a bug that may be changed in some future version.
+
+=item C<failed>
+
+The C<failed> command reports all distributions that failed on one of
+C<make>, C<test> or C<install> for some reason in the currently
+running shell session.
+
+=item Persistence between sessions
+
+If the C<YAML> or the C<YAML::Syck> module is installed a record of
+the internal state of all modules is written to disk after each step.
+The files contain a signature of the currently running perl version
+for later perusal.
+
+If the configurations variable C<build_dir_reuse> is set to a true
+value, then CPAN.pm reads the collected YAML files. If the stored
+signature matches the currently running perl, the stored state is
+loaded into memory such that persistence between sessions
+is effectively established.
+
+=item The C<force> and the C<fforce> pragma
+
+To speed things up in complex installation scenarios, CPAN.pm keeps
+track of what it has already done and refuses to do some things a
+second time. A C<get>, a C<make>, and an C<install> are not repeated.
+A C<test> is repeated only if the previous test was unsuccessful. The
+diagnostic message when CPAN.pm refuses to do something a second time
+is one of I<Has already been >C<unwrapped|made|tested successfully> or
+something similar. Another situation where CPAN refuses to act is an
+C<install> if the corresponding C<test> was not successful.
+
+In all these cases, the user can override this stubborn behaviour by
+prepending the command with the word force, for example:
+
+ cpan> force get Foo
+ cpan> force make AUTHOR/Bar-3.14.tar.gz
+ cpan> force test Baz
+ cpan> force install Acme::Meta
+
+Each I<forced> command is executed with the corresponding part of its
+memory erased.
+
+The C<fforce> pragma is a variant that emulates a C<force get> which
+erases the entire memory followed by the action specified, effectively
+restarting the whole get/make/test/install procedure from scratch.
+
+=item Lockfile
+
+Interactive sessions maintain a lockfile, by default C<~/.cpan/.lock>.
+Batch jobs can run without a lockfile and not disturb each other.
+
+The shell offers to run in I<downgraded mode> when another process is
+holding the lockfile. This is an experimental feature that is not yet
+tested very well. This second shell then does not write the history
+file, does not use the metadata file, and has a different prompt.
+
+=item Signals
+
+CPAN.pm installs signal handlers for SIGINT and SIGTERM. While you are
+in the cpan-shell, it is intended that you can press C<^C> anytime and
+return to the cpan-shell prompt. A SIGTERM will cause the cpan-shell
+to clean up and leave the shell loop. You can emulate the effect of a
+SIGTERM by sending two consecutive SIGINTs, which usually means by
+pressing C<^C> twice.
+
+CPAN.pm ignores SIGPIPE. If the user sets C<inactivity_timeout>, a
+SIGALRM is used during the run of the C<perl Makefile.PL> or C<perl
+Build.PL> subprocess. A SIGALRM is also used during module version
+parsing, and is controlled by C<version_timeout>.
+
+=back
+
+=head2 CPAN::Shell
+
+The commands available in the shell interface are methods in
+the package CPAN::Shell. If you enter the shell command, your
+input is split by the Text::ParseWords::shellwords() routine, which
+acts like most shells do. The first word is interpreted as the
+method to be invoked, and the rest of the words are treated as the method's arguments.
+Continuation lines are supported by ending a line with a
+literal backslash.
+
+=head2 autobundle
+
+C<autobundle> writes a bundle file into the
+C<$CPAN::Config-E<gt>{cpan_home}/Bundle> directory. The file contains
+a list of all modules that are both available from CPAN and currently
+installed within @INC. Duplicates of each distribution are suppressed.
+The name of the bundle file is based on the current date and a
+counter, e.g. F<Bundle/Snapshot_2012_05_21_00.pm>. This is installed
+again by running C<cpan Bundle::Snapshot_2012_05_21_00>, or installing
+C<Bundle::Snapshot_2012_05_21_00> from the CPAN shell.
+
+Return value: path to the written file.
+
+=head2 hosts
+
+Note: this feature is still in alpha state and may change in future
+versions of CPAN.pm
+
+This commands provides a statistical overview over recent download
+activities. The data for this is collected in the YAML file
+C<FTPstats.yml> in your C<cpan_home> directory. If no YAML module is
+configured or YAML not installed, no stats are provided.
+
+=over
+
+=item install_tested
+
+Install all distributions that have been tested successfully but have
+not yet been installed. See also C<is_tested>.
+
+=item is_tested
+
+List all build directories of distributions that have been tested
+successfully but have not yet been installed. See also
+C<install_tested>.
+
+=back
+
+=head2 mkmyconfig
+
+mkmyconfig() writes your own CPAN::MyConfig file into your C<~/.cpan/>
+directory so that you can save your own preferences instead of the
+system-wide ones.
+
+=head2 r [Module|/Regexp/]...
+
+scans current perl installation for modules that have a newer version
+available on CPAN and provides a list of them. If called without
+argument, all potential upgrades are listed; if called with arguments
+the list is filtered to the modules and regexps given as arguments.
+
+The listing looks something like this:
+
+ Package namespace installed latest in CPAN file
+ CPAN 1.94_64 1.9600 ANDK/CPAN-1.9600.tar.gz
+ CPAN::Reporter 1.1801 1.1902 DAGOLDEN/CPAN-Reporter-1.1902.tar.gz
+ YAML 0.70 0.73 INGY/YAML-0.73.tar.gz
+ YAML::Syck 1.14 1.17 AVAR/YAML-Syck-1.17.tar.gz
+ YAML::Tiny 1.44 1.50 ADAMK/YAML-Tiny-1.50.tar.gz
+ CGI 3.43 3.55 MARKSTOS/CGI.pm-3.55.tar.gz
+ Module::Build::YAML 1.40 1.41 DAGOLDEN/Module-Build-0.3800.tar.gz
+ TAP::Parser::Result::YAML 3.22 3.23 ANDYA/Test-Harness-3.23.tar.gz
+ YAML::XS 0.34 0.35 INGY/YAML-LibYAML-0.35.tar.gz
+
+It suppresses duplicates in the column C<in CPAN file> such that
+distributions with many upgradeable modules are listed only once.
+
+Note that the list is not sorted.
+
+=head2 recent ***EXPERIMENTAL COMMAND***
+
+The C<recent> command downloads a list of recent uploads to CPAN and
+displays them I<slowly>. While the command is running, a $SIG{INT}
+exits the loop after displaying the current item.
+
+B<Note>: This command requires XML::LibXML installed.
+
+B<Note>: This whole command currently is just a hack and will
+probably change in future versions of CPAN.pm, but the general
+approach will likely remain.
+
+B<Note>: See also L<smoke>
+
+=head2 recompile
+
+recompile() is a special command that takes no argument and
+runs the make/test/install cycle with brute force over all installed
+dynamically loadable extensions (a.k.a. XS modules) with 'force' in
+effect. The primary purpose of this command is to finish a network
+installation. Imagine you have a common source tree for two different
+architectures. You decide to do a completely independent fresh
+installation. You start on one architecture with the help of a Bundle
+file produced earlier. CPAN installs the whole Bundle for you, but
+when you try to repeat the job on the second architecture, CPAN
+responds with a C<"Foo up to date"> message for all modules. So you
+invoke CPAN's recompile on the second architecture and you're done.
+
+Another popular use for C<recompile> is to act as a rescue in case your
+perl breaks binary compatibility. If one of the modules that CPAN uses
+is in turn depending on binary compatibility (so you cannot run CPAN
+commands), then you should try the CPAN::Nox module for recovery.
+
+=head2 report Bundle|Distribution|Module
+
+The C<report> command temporarily turns on the C<test_report> config
+variable, then runs the C<force test> command with the given
+arguments. The C<force> pragma reruns the tests and repeats
+every step that might have failed before.
+
+=head2 smoke ***EXPERIMENTAL COMMAND***
+
+B<*** WARNING: this command downloads and executes software from CPAN to
+your computer of completely unknown status. You should never do
+this with your normal account and better have a dedicated well
+separated and secured machine to do this. ***>
+
+The C<smoke> command takes the list of recent uploads to CPAN as
+provided by the C<recent> command and tests them all. While the
+command is running $SIG{INT} is defined to mean that the current item
+shall be skipped.
+
+B<Note>: This whole command currently is just a hack and will
+probably change in future versions of CPAN.pm, but the general
+approach will likely remain.
+
+B<Note>: See also L<recent>
+
+=head2 upgrade [Module|/Regexp/]...
+
+The C<upgrade> command first runs an C<r> command with the given
+arguments and then installs the newest versions of all modules that
+were listed by that.
+
+=head2 The four C<CPAN::*> Classes: Author, Bundle, Module, Distribution
+
+Although it may be considered internal, the class hierarchy does matter
+for both users and programmer. CPAN.pm deals with the four
+classes mentioned above, and those classes all share a set of methods. Classical
+single polymorphism is in effect. A metaclass object registers all
+objects of all kinds and indexes them with a string. The strings
+referencing objects have a separated namespace (well, not completely
+separated):
+
+ Namespace Class
+
+ words containing a "/" (slash) Distribution
+ words starting with Bundle:: Bundle
+ everything else Module or Author
+
+Modules know their associated Distribution objects. They always refer
+to the most recent official release. Developers may mark their releases
+as unstable development versions (by inserting an underscore into the
+module version number which will also be reflected in the distribution
+name when you run 'make dist'), so the really hottest and newest
+distribution is not always the default. If a module Foo circulates
+on CPAN in both version 1.23 and 1.23_90, CPAN.pm offers a convenient
+way to install version 1.23 by saying
+
+ install Foo
+
+This would install the complete distribution file (say
+BAR/Foo-1.23.tar.gz) with all accompanying material. But if you would
+like to install version 1.23_90, you need to know where the
+distribution file resides on CPAN relative to the authors/id/
+directory. If the author is BAR, this might be BAR/Foo-1.23_90.tar.gz;
+so you would have to say
+
+ install BAR/Foo-1.23_90.tar.gz
+
+The first example will be driven by an object of the class
+CPAN::Module, the second by an object of class CPAN::Distribution.
+
+=head2 Integrating local directories
+
+Note: this feature is still in alpha state and may change in future
+versions of CPAN.pm
+
+Distribution objects are normally distributions from the CPAN, but
+there is a slightly degenerate case for Distribution objects, too, of
+projects held on the local disk. These distribution objects have the
+same name as the local directory and end with a dot. A dot by itself
+is also allowed for the current directory at the time CPAN.pm was
+used. All actions such as C<make>, C<test>, and C<install> are applied
+directly to that directory. This gives the command C<cpan .> an
+interesting touch: while the normal mantra of installing a CPAN module
+without CPAN.pm is one of
+
+ perl Makefile.PL perl Build.PL
+ ( go and get prerequisites )
+ make ./Build
+ make test ./Build test
+ make install ./Build install
+
+the command C<cpan .> does all of this at once. It figures out which
+of the two mantras is appropriate, fetches and installs all
+prerequisites, takes care of them recursively, and finally finishes the
+installation of the module in the current directory, be it a CPAN
+module or not.
+
+The typical usage case is for private modules or working copies of
+projects from remote repositories on the local disk.
+
+=head2 Redirection
+
+The usual shell redirection symbols C< | > and C<< > >> are recognized
+by the cpan shell B<only when surrounded by whitespace>. So piping to
+pager or redirecting output into a file works somewhat as in a normal
+shell, with the stipulation that you must type extra spaces.
+
+=head2 Plugin support ***EXPERIMENTAL***
+
+Plugins are objects that implement any of currently eight methods:
+
+ pre_get
+ post_get
+ pre_make
+ post_make
+ pre_test
+ post_test
+ pre_install
+ post_install
+
+The C<plugin_list> configuration parameter holds a list of strings of
+the form
+
+ Modulename=arg0,arg1,arg2,arg3,...
+
+eg:
+
+ CPAN::Plugin::Flurb=dir,/opt/pkgs/flurb/raw,verbose,1
+
+At run time, each listed plugin is instantiated as a singleton object
+by running the equivalent of this pseudo code:
+
+ my $plugin = <string representation from config>;
+ <generate Modulename and arguments from $plugin>;
+ my $p = $instance{$plugin} ||= Modulename->new($arg0,$arg1,...);
+
+The generated singletons are kept around from instantiation until the
+end of the shell session. <plugin_list> can be reconfigured at any
+time at run time. While the cpan shell is running, it checks all
+activated plugins at each of the 8 reference points listed above and
+runs the respective method if it is implemented for that object. The
+method is called with the active CPAN::Distribution object passed in
+as an argument.
+
+=head1 CONFIGURATION
+
+When the CPAN module is used for the first time, a configuration
+dialogue tries to determine a couple of site specific options. The
+result of the dialog is stored in a hash reference C< $CPAN::Config >
+in a file CPAN/Config.pm.
+
+Default values defined in the CPAN/Config.pm file can be
+overridden in a user specific file: CPAN/MyConfig.pm. Such a file is
+best placed in C<$HOME/.cpan/CPAN/MyConfig.pm>, because C<$HOME/.cpan> is
+added to the search path of the CPAN module before the use() or
+require() statements. The mkmyconfig command writes this file for you.
+
+The C<o conf> command has various bells and whistles:
+
+=over
+
+=item completion support
+
+If you have a ReadLine module installed, you can hit TAB at any point
+of the commandline and C<o conf> will offer you completion for the
+built-in subcommands and/or config variable names.
+
+=item displaying some help: o conf help
+
+Displays a short help
+
+=item displaying current values: o conf [KEY]
+
+Displays the current value(s) for this config variable. Without KEY,
+displays all subcommands and config variables.
+
+Example:
+
+ o conf shell
+
+If KEY starts and ends with a slash, the string in between is
+treated as a regular expression and only keys matching this regexp
+are displayed
+
+Example:
+
+ o conf /color/
+
+=item changing of scalar values: o conf KEY VALUE
+
+Sets the config variable KEY to VALUE. The empty string can be
+specified as usual in shells, with C<''> or C<"">
+
+Example:
+
+ o conf wget /usr/bin/wget
+
+=item changing of list values: o conf KEY SHIFT|UNSHIFT|PUSH|POP|SPLICE|LIST
+
+If a config variable name ends with C<list>, it is a list. C<o conf
+KEY shift> removes the first element of the list, C<o conf KEY pop>
+removes the last element of the list. C<o conf KEYS unshift LIST>
+prepends a list of values to the list, C<o conf KEYS push LIST>
+appends a list of valued to the list.
+
+Likewise, C<o conf KEY splice LIST> passes the LIST to the corresponding
+splice command.
+
+Finally, any other list of arguments is taken as a new list value for
+the KEY variable discarding the previous value.
+
+Examples:
+
+ o conf urllist unshift http://cpan.dev.local/CPAN
+ o conf urllist splice 3 1
+ o conf urllist http://cpan1.local http://cpan2.local ftp://ftp.perl.org
+
+=item reverting to saved: o conf defaults
+
+Reverts all config variables to the state in the saved config file.
+
+=item saving the config: o conf commit
+
+Saves all config variables to the current config file (CPAN/Config.pm
+or CPAN/MyConfig.pm that was loaded at start).
+
+=back
+
+The configuration dialog can be started any time later again by
+issuing the command C< o conf init > in the CPAN shell. A subset of
+the configuration dialog can be run by issuing C<o conf init WORD>
+where WORD is any valid config variable or a regular expression.
+
+=head2 Config Variables
+
+The following keys in the hash reference $CPAN::Config are
+currently defined:
+
+ applypatch path to external prg
+ auto_commit commit all changes to config variables to disk
+ build_cache size of cache for directories to build modules
+ build_dir locally accessible directory to build modules
+ build_dir_reuse boolean if distros in build_dir are persistent
+ build_requires_install_policy
+ to install or not to install when a module is
+ only needed for building. yes|no|ask/yes|ask/no
+ bzip2 path to external prg
+ cache_metadata use serializer to cache metadata
+ check_sigs if signatures should be verified
+ cleanup_after_install
+ remove build directory immediately after a
+ successful install
+ colorize_debug Term::ANSIColor attributes for debugging output
+ colorize_output boolean if Term::ANSIColor should colorize output
+ colorize_print Term::ANSIColor attributes for normal output
+ colorize_warn Term::ANSIColor attributes for warnings
+ commandnumber_in_prompt
+ boolean if you want to see current command number
+ commands_quote preferred character to use for quoting external
+ commands when running them. Defaults to double
+ quote on Windows, single tick everywhere else;
+ can be set to space to disable quoting
+ connect_to_internet_ok
+ whether to ask if opening a connection is ok before
+ urllist is specified
+ cpan_home local directory reserved for this package
+ curl path to external prg
+ dontload_hash DEPRECATED
+ dontload_list arrayref: modules in the list will not be
+ loaded by the CPAN::has_inst() routine
+ ftp path to external prg
+ ftp_passive if set, the environment variable FTP_PASSIVE is set
+ for downloads
+ ftp_proxy proxy host for ftp requests
+ ftpstats_period max number of days to keep download statistics
+ ftpstats_size max number of items to keep in the download statistics
+ getcwd see below
+ gpg path to external prg
+ gzip location of external program gzip
+ halt_on_failure stop processing after the first failure of queued
+ items or dependencies
+ histfile file to maintain history between sessions
+ histsize maximum number of lines to keep in histfile
+ http_proxy proxy host for http requests
+ inactivity_timeout breaks interactive Makefile.PLs or Build.PLs
+ after this many seconds inactivity. Set to 0 to
+ disable timeouts.
+ index_expire refetch index files after this many days
+ inhibit_startup_message
+ if true, suppress the startup message
+ keep_source_where directory in which to keep the source (if we do)
+ load_module_verbosity
+ report loading of optional modules used by CPAN.pm
+ lynx path to external prg
+ make location of external make program
+ make_arg arguments that should always be passed to 'make'
+ make_install_make_command
+ the make command for running 'make install', for
+ example 'sudo make'
+ make_install_arg same as make_arg for 'make install'
+ makepl_arg arguments passed to 'perl Makefile.PL'
+ mbuild_arg arguments passed to './Build'
+ mbuild_install_arg arguments passed to './Build install'
+ mbuild_install_build_command
+ command to use instead of './Build' when we are
+ in the install stage, for example 'sudo ./Build'
+ mbuildpl_arg arguments passed to 'perl Build.PL'
+ ncftp path to external prg
+ ncftpget path to external prg
+ no_proxy don't proxy to these hosts/domains (comma separated list)
+ pager location of external program more (or any pager)
+ password your password if you CPAN server wants one
+ patch path to external prg
+ patches_dir local directory containing patch files
+ perl5lib_verbosity verbosity level for PERL5LIB additions
+ plugin_list list of active hooks (see Plugin support above
+ and the CPAN::Plugin module)
+ prefer_external_tar
+ per default all untar operations are done with
+ Archive::Tar; by setting this variable to true
+ the external tar command is used if available
+ prefer_installer legal values are MB and EUMM: if a module comes
+ with both a Makefile.PL and a Build.PL, use the
+ former (EUMM) or the latter (MB); if the module
+ comes with only one of the two, that one will be
+ used no matter the setting
+ prerequisites_policy
+ what to do if you are missing module prerequisites
+ ('follow' automatically, 'ask' me, or 'ignore')
+ For 'follow', also sets PERL_AUTOINSTALL and
+ PERL_EXTUTILS_AUTOINSTALL for "--defaultdeps" if
+ not already set
+ prefs_dir local directory to store per-distro build options
+ proxy_user username for accessing an authenticating proxy
+ proxy_pass password for accessing an authenticating proxy
+ randomize_urllist add some randomness to the sequence of the urllist
+ recommends_policy whether recommended prerequisites should be included
+ scan_cache controls scanning of cache ('atstart', 'atexit' or 'never')
+ shell your favorite shell
+ show_unparsable_versions
+ boolean if r command tells which modules are versionless
+ show_upload_date boolean if commands should try to determine upload date
+ show_zero_versions boolean if r command tells for which modules $version==0
+ suggests_policy whether suggested prerequisites should be included
+ tar location of external program tar
+ tar_verbosity verbosity level for the tar command
+ term_is_latin deprecated: if true Unicode is translated to ISO-8859-1
+ (and nonsense for characters outside latin range)
+ term_ornaments boolean to turn ReadLine ornamenting on/off
+ test_report email test reports (if CPAN::Reporter is installed)
+ trust_test_report_history
+ skip testing when previously tested ok (according to
+ CPAN::Reporter history)
+ unzip location of external program unzip
+ urllist arrayref to nearby CPAN sites (or equivalent locations)
+ use_prompt_default set PERL_MM_USE_DEFAULT for configure/make/test/install
+ use_sqlite use CPAN::SQLite for metadata storage (fast and lean)
+ username your username if you CPAN server wants one
+ version_timeout stops version parsing after this many seconds.
+ Default is 15 secs. Set to 0 to disable.
+ wait_list arrayref to a wait server to try (See CPAN::WAIT)
+ wget path to external prg
+ yaml_load_code enable YAML code deserialisation via CPAN::DeferredCode
+ yaml_module which module to use to read/write YAML files
+
+You can set and query each of these options interactively in the cpan
+shell with the C<o conf> or the C<o conf init> command as specified below.
+
+=over 2
+
+=item C<o conf E<lt>scalar optionE<gt>>
+
+prints the current value of the I<scalar option>
+
+=item C<o conf E<lt>scalar optionE<gt> E<lt>valueE<gt>>
+
+Sets the value of the I<scalar option> to I<value>
+
+=item C<o conf E<lt>list optionE<gt>>
+
+prints the current value of the I<list option> in MakeMaker's
+neatvalue format.
+
+=item C<o conf E<lt>list optionE<gt> [shift|pop]>
+
+shifts or pops the array in the I<list option> variable
+
+=item C<o conf E<lt>list optionE<gt> [unshift|push|splice] E<lt>listE<gt>>
+
+works like the corresponding perl commands.
+
+=item interactive editing: o conf init [MATCH|LIST]
+
+Runs an interactive configuration dialog for matching variables.
+Without argument runs the dialog over all supported config variables.
+To specify a MATCH the argument must be enclosed by slashes.
+
+Examples:
+
+ o conf init ftp_passive ftp_proxy
+ o conf init /color/
+
+Note: this method of setting config variables often provides more
+explanation about the functioning of a variable than the manpage.
+
+=back
+
+=head2 CPAN::anycwd($path): Note on config variable getcwd
+
+CPAN.pm changes the current working directory often and needs to
+determine its own current working directory. By default it uses
+Cwd::cwd, but if for some reason this doesn't work on your system,
+configure alternatives according to the following table:
+
+=over 4
+
+=item cwd
+
+Calls Cwd::cwd
+
+=item getcwd
+
+Calls Cwd::getcwd
+
+=item fastcwd
+
+Calls Cwd::fastcwd
+
+=item getdcwd
+
+Calls Cwd::getdcwd
+
+=item backtickcwd
+
+Calls the external command cwd.
+
+=back
+
+=head2 Note on the format of the urllist parameter
+
+urllist parameters are URLs according to RFC 1738. We do a little
+guessing if your URL is not compliant, but if you have problems with
+C<file> URLs, please try the correct format. Either:
+
+ file://localhost/whatever/ftp/pub/CPAN/
+
+or
+
+ file:///home/ftp/pub/CPAN/
+
+=head2 The urllist parameter has CD-ROM support
+
+The C<urllist> parameter of the configuration table contains a list of
+URLs used for downloading. If the list contains any
+C<file> URLs, CPAN always tries there first. This
+feature is disabled for index files. So the recommendation for the
+owner of a CD-ROM with CPAN contents is: include your local, possibly
+outdated CD-ROM as a C<file> URL at the end of urllist, e.g.
+
+ o conf urllist push file://localhost/CDROM/CPAN
+
+CPAN.pm will then fetch the index files from one of the CPAN sites
+that come at the beginning of urllist. It will later check for each
+module to see whether there is a local copy of the most recent version.
+
+Another peculiarity of urllist is that the site that we could
+successfully fetch the last file from automatically gets a preference
+token and is tried as the first site for the next request. So if you
+add a new site at runtime it may happen that the previously preferred
+site will be tried another time. This means that if you want to disallow
+a site for the next transfer, it must be explicitly removed from
+urllist.
+
+=head2 Maintaining the urllist parameter
+
+If you have YAML.pm (or some other YAML module configured in
+C<yaml_module>) installed, CPAN.pm collects a few statistical data
+about recent downloads. You can view the statistics with the C<hosts>
+command or inspect them directly by looking into the C<FTPstats.yml>
+file in your C<cpan_home> directory.
+
+To get some interesting statistics, it is recommended that
+C<randomize_urllist> be set; this introduces some amount of
+randomness into the URL selection.
+
+=head2 The C<requires> and C<build_requires> dependency declarations
+
+Since CPAN.pm version 1.88_51 modules declared as C<build_requires> by
+a distribution are treated differently depending on the config
+variable C<build_requires_install_policy>. By setting
+C<build_requires_install_policy> to C<no>, such a module is not
+installed. It is only built and tested, and then kept in the list of
+tested but uninstalled modules. As such, it is available during the
+build of the dependent module by integrating the path to the
+C<blib/arch> and C<blib/lib> directories in the environment variable
+PERL5LIB. If C<build_requires_install_policy> is set ti C<yes>, then
+both modules declared as C<requires> and those declared as
+C<build_requires> are treated alike. By setting to C<ask/yes> or
+C<ask/no>, CPAN.pm asks the user and sets the default accordingly.
+
+=head2 Configuration for individual distributions (I<Distroprefs>)
+
+(B<Note:> This feature has been introduced in CPAN.pm 1.8854)
+
+Distributions on CPAN usually behave according to what we call the
+CPAN mantra. Or since the advent of Module::Build we should talk about
+two mantras:
+
+ perl Makefile.PL perl Build.PL
+ make ./Build
+ make test ./Build test
+ make install ./Build install
+
+But some modules cannot be built with this mantra. They try to get
+some extra data from the user via the environment, extra arguments, or
+interactively--thus disturbing the installation of large bundles like
+Phalanx100 or modules with many dependencies like Plagger.
+
+The distroprefs system of C<CPAN.pm> addresses this problem by
+allowing the user to specify extra informations and recipes in YAML
+files to either
+
+=over
+
+=item
+
+pass additional arguments to one of the four commands,
+
+=item
+
+set environment variables
+
+=item
+
+instantiate an Expect object that reads from the console, waits for
+some regular expressions and enters some answers
+
+=item
+
+temporarily override assorted C<CPAN.pm> configuration variables
+
+=item
+
+specify dependencies the original maintainer forgot
+
+=item
+
+disable the installation of an object altogether
+
+=back
+
+See the YAML and Data::Dumper files that come with the C<CPAN.pm>
+distribution in the C<distroprefs/> directory for examples.
+
+=head2 Filenames
+
+The YAML files themselves must have the C<.yml> extension; all other
+files are ignored (for two exceptions see I<Fallback Data::Dumper and
+Storable> below). The containing directory can be specified in
+C<CPAN.pm> in the C<prefs_dir> config variable. Try C<o conf init
+prefs_dir> in the CPAN shell to set and activate the distroprefs
+system.
+
+Every YAML file may contain arbitrary documents according to the YAML
+specification, and every document is treated as an entity that
+can specify the treatment of a single distribution.
+
+Filenames can be picked arbitrarily; C<CPAN.pm> always reads
+all files (in alphabetical order) and takes the key C<match> (see
+below in I<Language Specs>) as a hashref containing match criteria
+that determine if the current distribution matches the YAML document
+or not.
+
+=head2 Fallback Data::Dumper and Storable
+
+If neither your configured C<yaml_module> nor YAML.pm is installed,
+CPAN.pm falls back to using Data::Dumper and Storable and looks for
+files with the extensions C<.dd> or C<.st> in the C<prefs_dir>
+directory. These files are expected to contain one or more hashrefs.
+For Data::Dumper generated files, this is expected to be done with by
+defining C<$VAR1>, C<$VAR2>, etc. The YAML shell would produce these
+with the command
+
+ ysh < somefile.yml > somefile.dd
+
+For Storable files the rule is that they must be constructed such that
+C<Storable::retrieve(file)> returns an array reference and the array
+elements represent one distropref object each. The conversion from
+YAML would look like so:
+
+ perl -MYAML=LoadFile -MStorable=nstore -e '
+ @y=LoadFile(shift);
+ nstore(\@y, shift)' somefile.yml somefile.st
+
+In bootstrapping situations it is usually sufficient to translate only
+a few YAML files to Data::Dumper for crucial modules like
+C<YAML::Syck>, C<YAML.pm> and C<Expect.pm>. If you prefer Storable
+over Data::Dumper, remember to pull out a Storable version that writes
+an older format than all the other Storable versions that will need to
+read them.
+
+=head2 Blueprint
+
+The following example contains all supported keywords and structures
+with the exception of C<eexpect> which can be used instead of
+C<expect>.
+
+ ---
+ comment: "Demo"
+ match:
+ module: "Dancing::Queen"
+ distribution: "^CHACHACHA/Dancing-"
+ not_distribution: "\.zip$"
+ perl: "/usr/local/cariba-perl/bin/perl"
+ perlconfig:
+ archname: "freebsd"
+ not_cc: "gcc"
+ env:
+ DANCING_FLOOR: "Shubiduh"
+ disabled: 1
+ cpanconfig:
+ make: gmake
+ pl:
+ args:
+ - "--somearg=specialcase"
+
+ env: {}
+
+ expect:
+ - "Which is your favorite fruit"
+ - "apple\n"
+
+ make:
+ args:
+ - all
+ - extra-all
+
+ env: {}
+
+ expect: []
+
+ commandline: "echo SKIPPING make"
+
+ test:
+ args: []
+
+ env: {}
+
+ expect: []
+
+ install:
+ args: []
+
+ env:
+ WANT_TO_INSTALL: YES
+
+ expect:
+ - "Do you really want to install"
+ - "y\n"
+
+ patches:
+ - "ABCDE/Fedcba-3.14-ABCDE-01.patch"
+
+ depends:
+ configure_requires:
+ LWP: 5.8
+ build_requires:
+ Test::Exception: 0.25
+ requires:
+ Spiffy: 0.30
+
+
+=head2 Language Specs
+
+Every YAML document represents a single hash reference. The valid keys
+in this hash are as follows:
+
+=over
+
+=item comment [scalar]
+
+A comment
+
+=item cpanconfig [hash]
+
+Temporarily override assorted C<CPAN.pm> configuration variables.
+
+Supported are: C<build_requires_install_policy>, C<check_sigs>,
+C<make>, C<make_install_make_command>, C<prefer_installer>,
+C<test_report>. Please report as a bug when you need another one
+supported.
+
+=item depends [hash] *** EXPERIMENTAL FEATURE ***
+
+All three types, namely C<configure_requires>, C<build_requires>, and
+C<requires> are supported in the way specified in the META.yml
+specification. The current implementation I<merges> the specified
+dependencies with those declared by the package maintainer. In a
+future implementation this may be changed to override the original
+declaration.
+
+=item disabled [boolean]
+
+Specifies that this distribution shall not be processed at all.
+
+=item features [array] *** EXPERIMENTAL FEATURE ***
+
+Experimental implementation to deal with optional_features from
+META.yml. Still needs coordination with installer software and
+currently works only for META.yml declaring C<dynamic_config=0>. Use
+with caution.
+
+=item goto [string]
+
+The canonical name of a delegate distribution to install
+instead. Useful when a new version, although it tests OK itself,
+breaks something else or a developer release or a fork is already
+uploaded that is better than the last released version.
+
+=item install [hash]
+
+Processing instructions for the C<make install> or C<./Build install>
+phase of the CPAN mantra. See below under I<Processing Instructions>.
+
+=item make [hash]
+
+Processing instructions for the C<make> or C<./Build> phase of the
+CPAN mantra. See below under I<Processing Instructions>.
+
+=item match [hash]
+
+A hashref with one or more of the keys C<distribution>, C<module>,
+C<perl>, C<perlconfig>, and C<env> that specify whether a document is
+targeted at a specific CPAN distribution or installation.
+Keys prefixed with C<not_> negates the corresponding match.
+
+The corresponding values are interpreted as regular expressions. The
+C<distribution> related one will be matched against the canonical
+distribution name, e.g. "AUTHOR/Foo-Bar-3.14.tar.gz".
+
+The C<module> related one will be matched against I<all> modules
+contained in the distribution until one module matches.
+
+The C<perl> related one will be matched against C<$^X> (but with the
+absolute path).
+
+The value associated with C<perlconfig> is itself a hashref that is
+matched against corresponding values in the C<%Config::Config> hash
+living in the C<Config.pm> module.
+Keys prefixed with C<not_> negates the corresponding match.
+
+The value associated with C<env> is itself a hashref that is
+matched against corresponding values in the C<%ENV> hash.
+Keys prefixed with C<not_> negates the corresponding match.
+
+If more than one restriction of C<module>, C<distribution>, etc. is
+specified, the results of the separately computed match values must
+all match. If so, the hashref represented by the
+YAML document is returned as the preference structure for the current
+distribution.
+
+=item patches [array]
+
+An array of patches on CPAN or on the local disk to be applied in
+order via an external patch program. If the value for the C<-p>
+parameter is C<0> or C<1> is determined by reading the patch
+beforehand. The path to each patch is either an absolute path on the
+local filesystem or relative to a patch directory specified in the
+C<patches_dir> configuration variable or in the format of a canonical
+distro name. For examples please consult the distroprefs/ directory in
+the CPAN.pm distribution (these examples are not installed by
+default).
+
+Note: if the C<applypatch> program is installed and C<CPAN::Config>
+knows about it B<and> a patch is written by the C<makepatch> program,
+then C<CPAN.pm> lets C<applypatch> apply the patch. Both C<makepatch>
+and C<applypatch> are available from CPAN in the C<JV/makepatch-*>
+distribution.
+
+=item pl [hash]
+
+Processing instructions for the C<perl Makefile.PL> or C<perl
+Build.PL> phase of the CPAN mantra. See below under I<Processing
+Instructions>.
+
+=item test [hash]
+
+Processing instructions for the C<make test> or C<./Build test> phase
+of the CPAN mantra. See below under I<Processing Instructions>.
+
+=back
+
+=head2 Processing Instructions
+
+=over
+
+=item args [array]
+
+Arguments to be added to the command line
+
+=item commandline
+
+A full commandline to run via C<system()>.
+During execution, the environment variable PERL is set
+to $^X (but with an absolute path). If C<commandline> is specified,
+C<args> is not used.
+
+=item eexpect [hash]
+
+Extended C<expect>. This is a hash reference with four allowed keys,
+C<mode>, C<timeout>, C<reuse>, and C<talk>.
+
+You must install the C<Expect> module to use C<eexpect>. CPAN.pm
+does not install it for you.
+
+C<mode> may have the values C<deterministic> for the case where all
+questions come in the order written down and C<anyorder> for the case
+where the questions may come in any order. The default mode is
+C<deterministic>.
+
+C<timeout> denotes a timeout in seconds. Floating-point timeouts are
+OK. With C<mode=deterministic>, the timeout denotes the
+timeout per question; with C<mode=anyorder> it denotes the
+timeout per byte received from the stream or questions.
+
+C<talk> is a reference to an array that contains alternating questions
+and answers. Questions are regular expressions and answers are literal
+strings. The Expect module watches the stream from the
+execution of the external program (C<perl Makefile.PL>, C<perl
+Build.PL>, C<make>, etc.).
+
+For C<mode=deterministic>, the CPAN.pm injects the
+corresponding answer as soon as the stream matches the regular expression.
+
+For C<mode=anyorder> CPAN.pm answers a question as soon
+as the timeout is reached for the next byte in the input stream. In
+this mode you can use the C<reuse> parameter to decide what will
+happen with a question-answer pair after it has been used. In the
+default case (reuse=0) it is removed from the array, avoiding being
+used again accidentally. If you want to answer the
+question C<Do you really want to do that> several times, then it must
+be included in the array at least as often as you want this answer to
+be given. Setting the parameter C<reuse> to 1 makes this repetition
+unnecessary.
+
+=item env [hash]
+
+Environment variables to be set during the command
+
+=item expect [array]
+
+You must install the C<Expect> module to use C<expect>. CPAN.pm
+does not install it for you.
+
+C<< expect: <array> >> is a short notation for this C<eexpect>:
+
+ eexpect:
+ mode: deterministic
+ timeout: 15
+ talk: <array>
+
+=back
+
+=head2 Schema verification with C<Kwalify>
+
+If you have the C<Kwalify> module installed (which is part of the
+Bundle::CPANxxl), then all your distroprefs files are checked for
+syntactic correctness.
+
+=head2 Example Distroprefs Files
+
+C<CPAN.pm> comes with a collection of example YAML files. Note that these
+are really just examples and should not be used without care because
+they cannot fit everybody's purpose. After all, the authors of the
+packages that ask questions had a need to ask, so you should watch
+their questions and adjust the examples to your environment and your
+needs. You have been warned:-)
+
+=head1 PROGRAMMER'S INTERFACE
+
+If you do not enter the shell, shell commands are
+available both as methods (C<CPAN::Shell-E<gt>install(...)>) and as
+functions in the calling package (C<install(...)>). Before calling low-level
+commands, it makes sense to initialize components of CPAN you need, e.g.:
+
+ CPAN::HandleConfig->load;
+ CPAN::Shell::setup_output;
+ CPAN::Index->reload;
+
+High-level commands do such initializations automatically.
+
+There's currently only one class that has a stable interface -
+CPAN::Shell. All commands that are available in the CPAN shell are
+methods of the class CPAN::Shell. The arguments on the commandline are
+passed as arguments to the method.
+
+So if you take for example the shell command
+
+ notest install A B C
+
+the actually executed command is
+
+ CPAN::Shell->notest("install","A","B","C");
+
+Each of the commands that produce listings of modules (C<r>,
+C<autobundle>, C<u>) also return a list of the IDs of all modules
+within the list.
+
+=over 2
+
+=item expand($type,@things)
+
+The IDs of all objects available within a program are strings that can
+be expanded to the corresponding real objects with the
+C<CPAN::Shell-E<gt>expand("Module",@things)> method. Expand returns a
+list of CPAN::Module objects according to the C<@things> arguments
+given. In scalar context, it returns only the first element of the
+list.
+
+=item expandany(@things)
+
+Like expand, but returns objects of the appropriate type, i.e.
+CPAN::Bundle objects for bundles, CPAN::Module objects for modules, and
+CPAN::Distribution objects for distributions. Note: it does not expand
+to CPAN::Author objects.
+
+=item Programming Examples
+
+This enables the programmer to do operations that combine
+functionalities that are available in the shell.
+
+ # install everything that is outdated on my disk:
+ perl -MCPAN -e 'CPAN::Shell->install(CPAN::Shell->r)'
+
+ # install my favorite programs if necessary:
+ for $mod (qw(Net::FTP Digest::SHA Data::Dumper)) {
+ CPAN::Shell->install($mod);
+ }
+
+ # list all modules on my disk that have no VERSION number
+ for $mod (CPAN::Shell->expand("Module","/./")) {
+ next unless $mod->inst_file;
+ # MakeMaker convention for undefined $VERSION:
+ next unless $mod->inst_version eq "undef";
+ print "No VERSION in ", $mod->id, "\n";
+ }
+
+ # find out which distribution on CPAN contains a module:
+ print CPAN::Shell->expand("Module","Apache::Constants")->cpan_file
+
+Or if you want to schedule a I<cron> job to watch CPAN, you could list
+all modules that need updating. First a quick and dirty way:
+
+ perl -e 'use CPAN; CPAN::Shell->r;'
+
+If you don't want any output should all modules be
+up to date, parse the output of above command for the regular
+expression C</modules are up to date/> and decide to mail the output
+only if it doesn't match.
+
+If you prefer to do it more in a programmerish style in one single
+process, something like this may better suit you:
+
+ # list all modules on my disk that have newer versions on CPAN
+ for $mod (CPAN::Shell->expand("Module","/./")) {
+ next unless $mod->inst_file;
+ next if $mod->uptodate;
+ printf "Module %s is installed as %s, could be updated to %s from CPAN\n",
+ $mod->id, $mod->inst_version, $mod->cpan_version;
+ }
+
+If that gives too much output every day, you may want to
+watch only for three modules. You can write
+
+ for $mod (CPAN::Shell->expand("Module","/Apache|LWP|CGI/")) {
+
+as the first line instead. Or you can combine some of the above
+tricks:
+
+ # watch only for a new mod_perl module
+ $mod = CPAN::Shell->expand("Module","mod_perl");
+ exit if $mod->uptodate;
+ # new mod_perl arrived, let me know all update recommendations
+ CPAN::Shell->r;
+
+=back
+
+=head2 Methods in the other Classes
+
+=over 4
+
+=item CPAN::Author::as_glimpse()
+
+Returns a one-line description of the author
+
+=item CPAN::Author::as_string()
+
+Returns a multi-line description of the author
+
+=item CPAN::Author::email()
+
+Returns the author's email address
+
+=item CPAN::Author::fullname()
+
+Returns the author's name
+
+=item CPAN::Author::name()
+
+An alias for fullname
+
+=item CPAN::Bundle::as_glimpse()
+
+Returns a one-line description of the bundle
+
+=item CPAN::Bundle::as_string()
+
+Returns a multi-line description of the bundle
+
+=item CPAN::Bundle::clean()
+
+Recursively runs the C<clean> method on all items contained in the bundle.
+
+=item CPAN::Bundle::contains()
+
+Returns a list of objects' IDs contained in a bundle. The associated
+objects may be bundles, modules or distributions.
+
+=item CPAN::Bundle::force($method,@args)
+
+Forces CPAN to perform a task that it normally would have refused to
+do. Force takes as arguments a method name to be called and any number
+of additional arguments that should be passed to the called method.
+The internals of the object get the needed changes so that CPAN.pm
+does not refuse to take the action. The C<force> is passed recursively
+to all contained objects. See also the section above on the C<force>
+and the C<fforce> pragma.
+
+=item CPAN::Bundle::get()
+
+Recursively runs the C<get> method on all items contained in the bundle
+
+=item CPAN::Bundle::inst_file()
+
+Returns the highest installed version of the bundle in either @INC or
+C<< $CPAN::Config->{cpan_home} >>. Note that this is different from
+CPAN::Module::inst_file.
+
+=item CPAN::Bundle::inst_version()
+
+Like CPAN::Bundle::inst_file, but returns the $VERSION
+
+=item CPAN::Bundle::uptodate()
+
+Returns 1 if the bundle itself and all its members are up-to-date.
+
+=item CPAN::Bundle::install()
+
+Recursively runs the C<install> method on all items contained in the bundle
+
+=item CPAN::Bundle::make()
+
+Recursively runs the C<make> method on all items contained in the bundle
+
+=item CPAN::Bundle::readme()
+
+Recursively runs the C<readme> method on all items contained in the bundle
+
+=item CPAN::Bundle::test()
+
+Recursively runs the C<test> method on all items contained in the bundle
+
+=item CPAN::Distribution::as_glimpse()
+
+Returns a one-line description of the distribution
+
+=item CPAN::Distribution::as_string()
+
+Returns a multi-line description of the distribution
+
+=item CPAN::Distribution::author
+
+Returns the CPAN::Author object of the maintainer who uploaded this
+distribution
+
+=item CPAN::Distribution::pretty_id()
+
+Returns a string of the form "AUTHORID/TARBALL", where AUTHORID is the
+author's PAUSE ID and TARBALL is the distribution filename.
+
+=item CPAN::Distribution::base_id()
+
+Returns the distribution filename without any archive suffix. E.g
+"Foo-Bar-0.01"
+
+=item CPAN::Distribution::clean()
+
+Changes to the directory where the distribution has been unpacked and
+runs C<make clean> there.
+
+=item CPAN::Distribution::containsmods()
+
+Returns a list of IDs of modules contained in a distribution file.
+Works only for distributions listed in the 02packages.details.txt.gz
+file. This typically means that just most recent version of a
+distribution is covered.
+
+=item CPAN::Distribution::cvs_import()
+
+Changes to the directory where the distribution has been unpacked and
+runs something like
+
+ cvs -d $cvs_root import -m $cvs_log $cvs_dir $userid v$version
+
+there.
+
+=item CPAN::Distribution::dir()
+
+Returns the directory into which this distribution has been unpacked.
+
+=item CPAN::Distribution::force($method,@args)
+
+Forces CPAN to perform a task that it normally would have refused to
+do. Force takes as arguments a method name to be called and any number
+of additional arguments that should be passed to the called method.
+The internals of the object get the needed changes so that CPAN.pm
+does not refuse to take the action. See also the section above on the
+C<force> and the C<fforce> pragma.
+
+=item CPAN::Distribution::get()
+
+Downloads the distribution from CPAN and unpacks it. Does nothing if
+the distribution has already been downloaded and unpacked within the
+current session.
+
+=item CPAN::Distribution::install()
+
+Changes to the directory where the distribution has been unpacked and
+runs the external command C<make install> there. If C<make> has not
+yet been run, it will be run first. A C<make test> is issued in
+any case and if this fails, the install is cancelled. The
+cancellation can be avoided by letting C<force> run the C<install> for
+you.
+
+This install method only has the power to install the distribution if
+there are no dependencies in the way. To install an object along with all
+its dependencies, use CPAN::Shell->install.
+
+Note that install() gives no meaningful return value. See uptodate().
+
+=item CPAN::Distribution::isa_perl()
+
+Returns 1 if this distribution file seems to be a perl distribution.
+Normally this is derived from the file name only, but the index from
+CPAN can contain a hint to achieve a return value of true for other
+filenames too.
+
+=item CPAN::Distribution::look()
+
+Changes to the directory where the distribution has been unpacked and
+opens a subshell there. Exiting the subshell returns.
+
+=item CPAN::Distribution::make()
+
+First runs the C<get> method to make sure the distribution is
+downloaded and unpacked. Changes to the directory where the
+distribution has been unpacked and runs the external commands C<perl
+Makefile.PL> or C<perl Build.PL> and C<make> there.
+
+=item CPAN::Distribution::perldoc()
+
+Downloads the pod documentation of the file associated with a
+distribution (in HTML format) and runs it through the external
+command I<lynx> specified in C<< $CPAN::Config->{lynx} >>. If I<lynx>
+isn't available, it converts it to plain text with the external
+command I<html2text> and runs it through the pager specified
+in C<< $CPAN::Config->{pager} >>.
+
+=item CPAN::Distribution::prefs()
+
+Returns the hash reference from the first matching YAML file that the
+user has deposited in the C<prefs_dir/> directory. The first
+succeeding match wins. The files in the C<prefs_dir/> are processed
+alphabetically, and the canonical distro name (e.g.
+AUTHOR/Foo-Bar-3.14.tar.gz) is matched against the regular expressions
+stored in the $root->{match}{distribution} attribute value.
+Additionally all module names contained in a distribution are matched
+against the regular expressions in the $root->{match}{module} attribute
+value. The two match values are ANDed together. Each of the two
+attributes are optional.
+
+=item CPAN::Distribution::prereq_pm()
+
+Returns the hash reference that has been announced by a distribution
+as the C<requires> and C<build_requires> elements. These can be
+declared either by the C<META.yml> (if authoritative) or can be
+deposited after the run of C<Build.PL> in the file C<./_build/prereqs>
+or after the run of C<Makfile.PL> written as the C<PREREQ_PM> hash in
+a comment in the produced C<Makefile>. I<Note>: this method only works
+after an attempt has been made to C<make> the distribution. Returns
+undef otherwise.
+
+=item CPAN::Distribution::readme()
+
+Downloads the README file associated with a distribution and runs it
+through the pager specified in C<< $CPAN::Config->{pager} >>.
+
+=item CPAN::Distribution::reports()
+
+Downloads report data for this distribution from www.cpantesters.org
+and displays a subset of them.
+
+=item CPAN::Distribution::read_yaml()
+
+Returns the content of the META.yml of this distro as a hashref. Note:
+works only after an attempt has been made to C<make> the distribution.
+Returns undef otherwise. Also returns undef if the content of META.yml
+is not authoritative. (The rules about what exactly makes the content
+authoritative are still in flux.)
+
+=item CPAN::Distribution::test()
+
+Changes to the directory where the distribution has been unpacked and
+runs C<make test> there.
+
+=item CPAN::Distribution::uptodate()
+
+Returns 1 if all the modules contained in the distribution are
+up-to-date. Relies on containsmods.
+
+=item CPAN::Index::force_reload()
+
+Forces a reload of all indices.
+
+=item CPAN::Index::reload()
+
+Reloads all indices if they have not been read for more than
+C<< $CPAN::Config->{index_expire} >> days.
+
+=item CPAN::InfoObj::dump()
+
+CPAN::Author, CPAN::Bundle, CPAN::Module, and CPAN::Distribution
+inherit this method. It prints the data structure associated with an
+object. Useful for debugging. Note: the data structure is considered
+internal and thus subject to change without notice.
+
+=item CPAN::Module::as_glimpse()
+
+Returns a one-line description of the module in four columns: The
+first column contains the word C<Module>, the second column consists
+of one character: an equals sign if this module is already installed
+and up-to-date, a less-than sign if this module is installed but can be
+upgraded, and a space if the module is not installed. The third column
+is the name of the module and the fourth column gives maintainer or
+distribution information.
+
+=item CPAN::Module::as_string()
+
+Returns a multi-line description of the module
+
+=item CPAN::Module::clean()
+
+Runs a clean on the distribution associated with this module.
+
+=item CPAN::Module::cpan_file()
+
+Returns the filename on CPAN that is associated with the module.
+
+=item CPAN::Module::cpan_version()
+
+Returns the latest version of this module available on CPAN.
+
+=item CPAN::Module::cvs_import()
+
+Runs a cvs_import on the distribution associated with this module.
+
+=item CPAN::Module::description()
+
+Returns a 44 character description of this module. Only available for
+modules listed in The Module List (CPAN/modules/00modlist.long.html
+or 00modlist.long.txt.gz)
+
+=item CPAN::Module::distribution()
+
+Returns the CPAN::Distribution object that contains the current
+version of this module.
+
+=item CPAN::Module::dslip_status()
+
+Returns a hash reference. The keys of the hash are the letters C<D>,
+C<S>, C<L>, C<I>, and <P>, for development status, support level,
+language, interface and public licence respectively. The data for the
+DSLIP status are collected by pause.perl.org when authors register
+their namespaces. The values of the 5 hash elements are one-character
+words whose meaning is described in the table below. There are also 5
+hash elements C<DV>, C<SV>, C<LV>, C<IV>, and <PV> that carry a more
+verbose value of the 5 status variables.
+
+Where the 'DSLIP' characters have the following meanings:
+
+ D - Development Stage (Note: *NO IMPLIED TIMESCALES*):
+ i - Idea, listed to gain consensus or as a placeholder
+ c - under construction but pre-alpha (not yet released)
+ a/b - Alpha/Beta testing
+ R - Released
+ M - Mature (no rigorous definition)
+ S - Standard, supplied with Perl 5
+
+ S - Support Level:
+ m - Mailing-list
+ d - Developer
+ u - Usenet newsgroup comp.lang.perl.modules
+ n - None known, try comp.lang.perl.modules
+ a - abandoned; volunteers welcome to take over maintenance
+
+ L - Language Used:
+ p - Perl-only, no compiler needed, should be platform independent
+ c - C and perl, a C compiler will be needed
+ h - Hybrid, written in perl with optional C code, no compiler needed
+ + - C++ and perl, a C++ compiler will be needed
+ o - perl and another language other than C or C++
+
+ I - Interface Style
+ f - plain Functions, no references used
+ h - hybrid, object and function interfaces available
+ n - no interface at all (huh?)
+ r - some use of unblessed References or ties
+ O - Object oriented using blessed references and/or inheritance
+
+ P - Public License
+ p - Standard-Perl: user may choose between GPL and Artistic
+ g - GPL: GNU General Public License
+ l - LGPL: "GNU Lesser General Public License" (previously known as
+ "GNU Library General Public License")
+ b - BSD: The BSD License
+ a - Artistic license alone
+ 2 - Artistic license 2.0 or later
+ o - open source: approved by www.opensource.org
+ d - allows distribution without restrictions
+ r - restricted distribution
+ n - no license at all
+
+=item CPAN::Module::force($method,@args)
+
+Forces CPAN to perform a task it would normally refuse to
+do. Force takes as arguments a method name to be invoked and any number
+of additional arguments to pass that method.
+The internals of the object get the needed changes so that CPAN.pm
+does not refuse to take the action. See also the section above on the
+C<force> and the C<fforce> pragma.
+
+=item CPAN::Module::get()
+
+Runs a get on the distribution associated with this module.
+
+=item CPAN::Module::inst_file()
+
+Returns the filename of the module found in @INC. The first file found
+is reported, just as perl itself stops searching @INC once it finds a
+module.
+
+=item CPAN::Module::available_file()
+
+Returns the filename of the module found in PERL5LIB or @INC. The
+first file found is reported. The advantage of this method over
+C<inst_file> is that modules that have been tested but not yet
+installed are included because PERL5LIB keeps track of tested modules.
+
+=item CPAN::Module::inst_version()
+
+Returns the version number of the installed module in readable format.
+
+=item CPAN::Module::available_version()
+
+Returns the version number of the available module in readable format.
+
+=item CPAN::Module::install()
+
+Runs an C<install> on the distribution associated with this module.
+
+=item CPAN::Module::look()
+
+Changes to the directory where the distribution associated with this
+module has been unpacked and opens a subshell there. Exiting the
+subshell returns.
+
+=item CPAN::Module::make()
+
+Runs a C<make> on the distribution associated with this module.
+
+=item CPAN::Module::manpage_headline()
+
+If module is installed, peeks into the module's manpage, reads the
+headline, and returns it. Moreover, if the module has been downloaded
+within this session, does the equivalent on the downloaded module even
+if it hasn't been installed yet.
+
+=item CPAN::Module::perldoc()
+
+Runs a C<perldoc> on this module.
+
+=item CPAN::Module::readme()
+
+Runs a C<readme> on the distribution associated with this module.
+
+=item CPAN::Module::reports()
+
+Calls the reports() method on the associated distribution object.
+
+=item CPAN::Module::test()
+
+Runs a C<test> on the distribution associated with this module.
+
+=item CPAN::Module::uptodate()
+
+Returns 1 if the module is installed and up-to-date.
+
+=item CPAN::Module::userid()
+
+Returns the author's ID of the module.
+
+=back
+
+=head2 Cache Manager
+
+Currently the cache manager only keeps track of the build directory
+($CPAN::Config->{build_dir}). It is a simple FIFO mechanism that
+deletes complete directories below C<build_dir> as soon as the size of
+all directories there gets bigger than $CPAN::Config->{build_cache}
+(in MB). The contents of this cache may be used for later
+re-installations that you intend to do manually, but will never be
+trusted by CPAN itself. This is due to the fact that the user might
+use these directories for building modules on different architectures.
+
+There is another directory ($CPAN::Config->{keep_source_where}) where
+the original distribution files are kept. This directory is not
+covered by the cache manager and must be controlled by the user. If
+you choose to have the same directory as build_dir and as
+keep_source_where directory, then your sources will be deleted with
+the same fifo mechanism.
+
+=head2 Bundles
+
+A bundle is just a perl module in the namespace Bundle:: that does not
+define any functions or methods. It usually only contains documentation.
+
+It starts like a perl module with a package declaration and a $VERSION
+variable. After that the pod section looks like any other pod with the
+only difference being that I<one special pod section> exists starting with
+(verbatim):
+
+ =head1 CONTENTS
+
+In this pod section each line obeys the format
+
+ Module_Name [Version_String] [- optional text]
+
+The only required part is the first field, the name of a module
+(e.g. Foo::Bar, i.e. I<not> the name of the distribution file). The rest
+of the line is optional. The comment part is delimited by a dash just
+as in the man page header.
+
+The distribution of a bundle should follow the same convention as
+other distributions.
+
+Bundles are treated specially in the CPAN package. If you say 'install
+Bundle::Tkkit' (assuming such a bundle exists), CPAN will install all
+the modules in the CONTENTS section of the pod. You can install your
+own Bundles locally by placing a conformant Bundle file somewhere into
+your @INC path. The autobundle() command which is available in the
+shell interface does that for you by including all currently installed
+modules in a snapshot bundle file.
+
+=head1 PREREQUISITES
+
+The CPAN program is trying to depend on as little as possible so the
+user can use it in hostile environment. It works better the more goodies
+the environment provides. For example if you try in the CPAN shell
+
+ install Bundle::CPAN
+
+or
+
+ install Bundle::CPANxxl
+
+you will find the shell more convenient than the bare shell before.
+
+If you have a local mirror of CPAN and can access all files with
+"file:" URLs, then you only need a perl later than perl5.003 to run
+this module. Otherwise Net::FTP is strongly recommended. LWP may be
+required for non-UNIX systems, or if your nearest CPAN site is
+associated with a URL that is not C<ftp:>.
+
+If you have neither Net::FTP nor LWP, there is a fallback mechanism
+implemented for an external ftp command or for an external lynx
+command.
+
+=head1 UTILITIES
+
+=head2 Finding packages and VERSION
+
+This module presumes that all packages on CPAN
+
+=over 2
+
+=item *
+
+declare their $VERSION variable in an easy to parse manner. This
+prerequisite can hardly be relaxed because it consumes far too much
+memory to load all packages into the running program just to determine
+the $VERSION variable. Currently all programs that are dealing with
+version use something like this
+
+ perl -MExtUtils::MakeMaker -le \
+ 'print MM->parse_version(shift)' filename
+
+If you are author of a package and wonder if your $VERSION can be
+parsed, please try the above method.
+
+=item *
+
+come as compressed or gzipped tarfiles or as zip files and contain a
+C<Makefile.PL> or C<Build.PL> (well, we try to handle a bit more, but
+with little enthusiasm).
+
+=back
+
+=head2 Debugging
+
+Debugging this module is more than a bit complex due to interference from
+the software producing the indices on CPAN, the mirroring process on CPAN,
+packaging, configuration, synchronicity, and even (gasp!) due to bugs
+within the CPAN.pm module itself.
+
+For debugging the code of CPAN.pm itself in interactive mode, some
+debugging aid can be turned on for most packages within
+CPAN.pm with one of
+
+=over 2
+
+=item o debug package...
+
+sets debug mode for packages.
+
+=item o debug -package...
+
+unsets debug mode for packages.
+
+=item o debug all
+
+turns debugging on for all packages.
+
+=item o debug number
+
+=back
+
+which sets the debugging packages directly. Note that C<o debug 0>
+turns debugging off.
+
+What seems a successful strategy is the combination of C<reload
+cpan> and the debugging switches. Add a new debug statement while
+running in the shell and then issue a C<reload cpan> and see the new
+debugging messages immediately without losing the current context.
+
+C<o debug> without an argument lists the valid package names and the
+current set of packages in debugging mode. C<o debug> has built-in
+completion support.
+
+For debugging of CPAN data there is the C<dump> command which takes
+the same arguments as make/test/install and outputs each object's
+Data::Dumper dump. If an argument looks like a perl variable and
+contains one of C<$>, C<@> or C<%>, it is eval()ed and fed to
+Data::Dumper directly.
+
+=head2 Floppy, Zip, Offline Mode
+
+CPAN.pm works nicely without network access, too. If you maintain machines
+that are not networked at all, you should consider working with C<file:>
+URLs. You'll have to collect your modules somewhere first. So
+you might use CPAN.pm to put together all you need on a networked
+machine. Then copy the $CPAN::Config->{keep_source_where} (but not
+$CPAN::Config->{build_dir}) directory on a floppy. This floppy is kind
+of a personal CPAN. CPAN.pm on the non-networked machines works nicely
+with this floppy. See also below the paragraph about CD-ROM support.
+
+=head2 Basic Utilities for Programmers
+
+=over 2
+
+=item has_inst($module)
+
+Returns true if the module is installed. Used to load all modules into
+the running CPAN.pm that are considered optional. The config variable
+C<dontload_list> intercepts the C<has_inst()> call such
+that an optional module is not loaded despite being available. For
+example, the following command will prevent C<YAML.pm> from being
+loaded:
+
+ cpan> o conf dontload_list push YAML
+
+See the source for details.
+
+=item use_inst($module)
+
+Similary to L<has_inst()> tries to load optional library but also dies if
+library is not available
+
+=item has_usable($module)
+
+Returns true if the module is installed and in a usable state. Only
+useful for a handful of modules that are used internally. See the
+source for details.
+
+=item instance($module)
+
+The constructor for all the singletons used to represent modules,
+distributions, authors, and bundles. If the object already exists, this
+method returns the object; otherwise, it calls the constructor.
+
+=item frontend()
+
+=item frontend($new_frontend)
+
+Getter/setter for frontend object. Method just allows to subclass CPAN.pm.
+
+=back
+
+=head1 SECURITY
+
+There's no strong security layer in CPAN.pm. CPAN.pm helps you to
+install foreign, unmasked, unsigned code on your machine. We compare
+to a checksum that comes from the net just as the distribution file
+itself. But we try to make it easy to add security on demand:
+
+=head2 Cryptographically signed modules
+
+Since release 1.77, CPAN.pm has been able to verify cryptographically
+signed module distributions using Module::Signature. The CPAN modules
+can be signed by their authors, thus giving more security. The simple
+unsigned MD5 checksums that were used before by CPAN protect mainly
+against accidental file corruption.
+
+You will need to have Module::Signature installed, which in turn
+requires that you have at least one of Crypt::OpenPGP module or the
+command-line F<gpg> tool installed.
+
+You will also need to be able to connect over the Internet to the public
+key servers, like pgp.mit.edu, and their port 11731 (the HKP protocol).
+
+The configuration parameter check_sigs is there to turn signature
+checking on or off.
+
+=head1 EXPORT
+
+Most functions in package CPAN are exported by default. The reason
+for this is that the primary use is intended for the cpan shell or for
+one-liners.
+
+=head1 ENVIRONMENT
+
+When the CPAN shell enters a subshell via the look command, it sets
+the environment CPAN_SHELL_LEVEL to 1, or increments that variable if it is
+already set.
+
+When CPAN runs, it sets the environment variable PERL5_CPAN_IS_RUNNING
+to the ID of the running process. It also sets
+PERL5_CPANPLUS_IS_RUNNING to prevent runaway processes which could
+happen with older versions of Module::Install.
+
+When running C<perl Makefile.PL>, the environment variable
+C<PERL5_CPAN_IS_EXECUTING> is set to the full path of the
+C<Makefile.PL> that is being executed. This prevents runaway processes
+with newer versions of Module::Install.
+
+When the config variable ftp_passive is set, all downloads will be run
+with the environment variable FTP_PASSIVE set to this value. This is
+in general a good idea as it influences both Net::FTP and LWP based
+connections. The same effect can be achieved by starting the cpan
+shell with this environment variable set. For Net::FTP alone, one can
+also always set passive mode by running libnetcfg.
+
+=head1 POPULATE AN INSTALLATION WITH LOTS OF MODULES
+
+Populating a freshly installed perl with one's favorite modules is pretty
+easy if you maintain a private bundle definition file. To get a useful
+blueprint of a bundle definition file, the command autobundle can be used
+on the CPAN shell command line. This command writes a bundle definition
+file for all modules installed for the current perl
+interpreter. It's recommended to run this command once only, and from then
+on maintain the file manually under a private name, say
+Bundle/my_bundle.pm. With a clever bundle file you can then simply say
+
+ cpan> install Bundle::my_bundle
+
+then answer a few questions and go out for coffee (possibly
+even in a different city).
+
+Maintaining a bundle definition file means keeping track of two
+things: dependencies and interactivity. CPAN.pm sometimes fails on
+calculating dependencies because not all modules define all MakeMaker
+attributes correctly, so a bundle definition file should specify
+prerequisites as early as possible. On the other hand, it's
+annoying that so many distributions need some interactive configuring. So
+what you can try to accomplish in your private bundle file is to have the
+packages that need to be configured early in the file and the gentle
+ones later, so you can go out for coffee after a few minutes and leave CPAN.pm
+to churn away unattended.
+
+=head1 WORKING WITH CPAN.pm BEHIND FIREWALLS
+
+Thanks to Graham Barr for contributing the following paragraphs about
+the interaction between perl, and various firewall configurations. For
+further information on firewalls, it is recommended to consult the
+documentation that comes with the I<ncftp> program. If you are unable to
+go through the firewall with a simple Perl setup, it is likely
+that you can configure I<ncftp> so that it works through your firewall.
+
+=head2 Three basic types of firewalls
+
+Firewalls can be categorized into three basic types.
+
+=over 4
+
+=item http firewall
+
+This is when the firewall machine runs a web server, and to access the
+outside world, you must do so via that web server. If you set environment
+variables like http_proxy or ftp_proxy to values beginning with http://,
+or in your web browser you've proxy information set, then you know
+you are running behind an http firewall.
+
+To access servers outside these types of firewalls with perl (even for
+ftp), you need LWP or HTTP::Tiny.
+
+=item ftp firewall
+
+This where the firewall machine runs an ftp server. This kind of
+firewall will only let you access ftp servers outside the firewall.
+This is usually done by connecting to the firewall with ftp, then
+entering a username like "user@outside.host.com".
+
+To access servers outside these type of firewalls with perl, you
+need Net::FTP.
+
+=item One-way visibility
+
+One-way visibility means these firewalls try to make themselves
+invisible to users inside the firewall. An FTP data connection is
+normally created by sending your IP address to the remote server and then
+listening for the return connection. But the remote server will not be able to
+connect to you because of the firewall. For these types of firewall,
+FTP connections need to be done in a passive mode.
+
+There are two that I can think off.
+
+=over 4
+
+=item SOCKS
+
+If you are using a SOCKS firewall, you will need to compile perl and link
+it with the SOCKS library. This is what is normally called a 'socksified'
+perl. With this executable you will be able to connect to servers outside
+the firewall as if it were not there.
+
+=item IP Masquerade
+
+This is when the firewall implemented in the kernel (via NAT, or networking
+address translation), it allows you to hide a complete network behind one
+IP address. With this firewall no special compiling is needed as you can
+access hosts directly.
+
+For accessing ftp servers behind such firewalls you usually need to
+set the environment variable C<FTP_PASSIVE> or the config variable
+ftp_passive to a true value.
+
+=back
+
+=back
+
+=head2 Configuring lynx or ncftp for going through a firewall
+
+If you can go through your firewall with e.g. lynx, presumably with a
+command such as
+
+ /usr/local/bin/lynx -pscott:tiger
+
+then you would configure CPAN.pm with the command
+
+ o conf lynx "/usr/local/bin/lynx -pscott:tiger"
+
+That's all. Similarly for ncftp or ftp, you would configure something
+like
+
+ o conf ncftp "/usr/bin/ncftp -f /home/scott/ncftplogin.cfg"
+
+Your mileage may vary...
+
+=head1 FAQ
+
+=over 4
+
+=item 1)
+
+I installed a new version of module X but CPAN keeps saying,
+I have the old version installed
+
+Probably you B<do> have the old version installed. This can
+happen if a module installs itself into a different directory in the
+@INC path than it was previously installed. This is not really a
+CPAN.pm problem, you would have the same problem when installing the
+module manually. The easiest way to prevent this behaviour is to add
+the argument C<UNINST=1> to the C<make install> call, and that is why
+many people add this argument permanently by configuring
+
+ o conf make_install_arg UNINST=1
+
+=item 2)
+
+So why is UNINST=1 not the default?
+
+Because there are people who have their precise expectations about who
+may install where in the @INC path and who uses which @INC array. In
+fine tuned environments C<UNINST=1> can cause damage.
+
+=item 3)
+
+I want to clean up my mess, and install a new perl along with
+all modules I have. How do I go about it?
+
+Run the autobundle command for your old perl and optionally rename the
+resulting bundle file (e.g. Bundle/mybundle.pm), install the new perl
+with the Configure option prefix, e.g.
+
+ ./Configure -Dprefix=/usr/local/perl-5.6.78.9
+
+Install the bundle file you produced in the first step with something like
+
+ cpan> install Bundle::mybundle
+
+and you're done.
+
+=item 4)
+
+When I install bundles or multiple modules with one command
+there is too much output to keep track of.
+
+You may want to configure something like
+
+ o conf make_arg "| tee -ai /root/.cpan/logs/make.out"
+ o conf make_install_arg "| tee -ai /root/.cpan/logs/make_install.out"
+
+so that STDOUT is captured in a file for later inspection.
+
+
+=item 5)
+
+I am not root, how can I install a module in a personal directory?
+
+As of CPAN 1.9463, if you do not have permission to write the default perl
+library directories, CPAN's configuration process will ask you whether
+you want to bootstrap <local::lib>, which makes keeping a personal
+perl library directory easy.
+
+Another thing you should bear in mind is that the UNINST parameter can
+be dangerous when you are installing into a private area because you
+might accidentally remove modules that other people depend on that are
+not using the private area.
+
+=item 6)
+
+How to get a package, unwrap it, and make a change before building it?
+
+Have a look at the C<look> (!) command.
+
+=item 7)
+
+I installed a Bundle and had a couple of fails. When I
+retried, everything resolved nicely. Can this be fixed to work
+on first try?
+
+The reason for this is that CPAN does not know the dependencies of all
+modules when it starts out. To decide about the additional items to
+install, it just uses data found in the META.yml file or the generated
+Makefile. An undetected missing piece breaks the process. But it may
+well be that your Bundle installs some prerequisite later than some
+depending item and thus your second try is able to resolve everything.
+Please note, CPAN.pm does not know the dependency tree in advance and
+cannot sort the queue of things to install in a topologically correct
+order. It resolves perfectly well B<if> all modules declare the
+prerequisites correctly with the PREREQ_PM attribute to MakeMaker or
+the C<requires> stanza of Module::Build. For bundles which fail and
+you need to install often, it is recommended to sort the Bundle
+definition file manually.
+
+=item 8)
+
+In our intranet, we have many modules for internal use. How
+can I integrate these modules with CPAN.pm but without uploading
+the modules to CPAN?
+
+Have a look at the CPAN::Site module.
+
+=item 9)
+
+When I run CPAN's shell, I get an error message about things in my
+C</etc/inputrc> (or C<~/.inputrc>) file.
+
+These are readline issues and can only be fixed by studying readline
+configuration on your architecture and adjusting the referenced file
+accordingly. Please make a backup of the C</etc/inputrc> or C<~/.inputrc>
+and edit them. Quite often harmless changes like uppercasing or
+lowercasing some arguments solves the problem.
+
+=item 10)
+
+Some authors have strange characters in their names.
+
+Internally CPAN.pm uses the UTF-8 charset. If your terminal is
+expecting ISO-8859-1 charset, a converter can be activated by setting
+term_is_latin to a true value in your config file. One way of doing so
+would be
+
+ cpan> o conf term_is_latin 1
+
+If other charset support is needed, please file a bug report against
+CPAN.pm at rt.cpan.org and describe your needs. Maybe we can extend
+the support or maybe UTF-8 terminals become widely available.
+
+Note: this config variable is deprecated and will be removed in a
+future version of CPAN.pm. It will be replaced with the conventions
+around the family of $LANG and $LC_* environment variables.
+
+=item 11)
+
+When an install fails for some reason and then I correct the error
+condition and retry, CPAN.pm refuses to install the module, saying
+C<Already tried without success>.
+
+Use the force pragma like so
+
+ force install Foo::Bar
+
+Or you can use
+
+ look Foo::Bar
+
+and then C<make install> directly in the subshell.
+
+=item 12)
+
+How do I install a "DEVELOPER RELEASE" of a module?
+
+By default, CPAN will install the latest non-developer release of a
+module. If you want to install a dev release, you have to specify the
+partial path starting with the author id to the tarball you wish to
+install, like so:
+
+ cpan> install KWILLIAMS/Module-Build-0.27_07.tar.gz
+
+Note that you can use the C<ls> command to get this path listed.
+
+=item 13)
+
+How do I install a module and all its dependencies from the commandline,
+without being prompted for anything, despite my CPAN configuration
+(or lack thereof)?
+
+CPAN uses ExtUtils::MakeMaker's prompt() function to ask its questions, so
+if you set the PERL_MM_USE_DEFAULT environment variable, you shouldn't be
+asked any questions at all (assuming the modules you are installing are
+nice about obeying that variable as well):
+
+ % PERL_MM_USE_DEFAULT=1 perl -MCPAN -e 'install My::Module'
+
+=item 14)
+
+How do I create a Module::Build based Build.PL derived from an
+ExtUtils::MakeMaker focused Makefile.PL?
+
+http://search.cpan.org/dist/Module-Build-Convert/
+
+=item 15)
+
+I'm frequently irritated with the CPAN shell's inability to help me
+select a good mirror.
+
+CPAN can now help you select a "good" mirror, based on which ones have the
+lowest 'ping' round-trip times. From the shell, use the command 'o conf init
+urllist' and allow CPAN to automatically select mirrors for you.
+
+Beyond that help, the urllist config parameter is yours. You can add and remove
+sites at will. You should find out which sites have the best up-to-dateness,
+bandwidth, reliability, etc. and are topologically close to you. Some people
+prefer fast downloads, others up-to-dateness, others reliability. You decide
+which to try in which order.
+
+Henk P. Penning maintains a site that collects data about CPAN sites:
+
+ http://mirrors.cpan.org/
+
+Also, feel free to play with experimental features. Run
+
+ o conf init randomize_urllist ftpstats_period ftpstats_size
+
+and choose your favorite parameters. After a few downloads running the
+C<hosts> command will probably assist you in choosing the best mirror
+sites.
+
+=item 16)
+
+Why do I get asked the same questions every time I start the shell?
+
+You can make your configuration changes permanent by calling the
+command C<o conf commit>. Alternatively set the C<auto_commit>
+variable to true by running C<o conf init auto_commit> and answering
+the following question with yes.
+
+=item 17)
+
+Older versions of CPAN.pm had the original root directory of all
+tarballs in the build directory. Now there are always random
+characters appended to these directory names. Why was this done?
+
+The random characters are provided by File::Temp and ensure that each
+module's individual build directory is unique. This makes running
+CPAN.pm in concurrent processes simultaneously safe.
+
+=item 18)
+
+Speaking of the build directory. Do I have to clean it up myself?
+
+You have the choice to set the config variable C<scan_cache> to
+C<never>. Then you must clean it up yourself. The other possible
+values, C<atstart> and C<atexit> clean up the build directory when you
+start (or more precisely, after the first extraction into the build
+directory) or exit the CPAN shell, respectively. If you never start up
+the CPAN shell, you probably also have to clean up the build directory
+yourself.
+
+=back
+
+=head1 COMPATIBILITY
+
+=head2 OLD PERL VERSIONS
+
+CPAN.pm is regularly tested to run under 5.005 and assorted
+newer versions. It is getting more and more difficult to get the
+minimal prerequisites working on older perls. It is close to
+impossible to get the whole Bundle::CPAN working there. If you're in
+the position to have only these old versions, be advised that CPAN is
+designed to work fine without the Bundle::CPAN installed.
+
+To get things going, note that GBARR/Scalar-List-Utils-1.18.tar.gz is
+compatible with ancient perls and that File::Temp is listed as a
+prerequisite but CPAN has reasonable workarounds if it is missing.
+
+=head2 CPANPLUS
+
+This module and its competitor, the CPANPLUS module, are both much
+cooler than the other. CPAN.pm is older. CPANPLUS was designed to be
+more modular, but it was never intended to be compatible with CPAN.pm.
+
+=head2 CPANMINUS
+
+In the year 2010 App::cpanminus was launched as a new approach to a
+cpan shell with a considerably smaller footprint. Very cool stuff.
+
+=head1 SECURITY ADVICE
+
+This software enables you to upgrade software on your computer and so
+is inherently dangerous because the newly installed software may
+contain bugs and may alter the way your computer works or even make it
+unusable. Please consider backing up your data before every upgrade.
+
+=head1 BUGS
+
+Please report bugs via L<http://rt.cpan.org/>
+
+Before submitting a bug, please make sure that the traditional method
+of building a Perl module package from a shell by following the
+installation instructions of that package still works in your
+environment.
+
+=head1 AUTHOR
+
+Andreas Koenig C<< <andk@cpan.org> >>
+
+=head1 LICENSE
+
+This program is free software; you can redistribute it and/or
+modify it under the same terms as Perl itself.
+
+See L<http://www.perl.com/perl/misc/Artistic.html>
+
+=head1 TRANSLATIONS
+
+Kawai,Takanori provides a Japanese translation of a very old version
+of this manpage at
+L<http://homepage3.nifty.com/hippo2000/perltips/CPAN.htm>
+
+=head1 SEE ALSO
+
+Many people enter the CPAN shell by running the L<cpan> utility
+program which is installed in the same directory as perl itself. So if
+you have this directory in your PATH variable (or some equivalent in
+your operating system) then typing C<cpan> in a console window will
+work for you as well. Above that the utility provides several
+commandline shortcuts.
+
+melezhik (Alexey) sent me a link where he published a chef recipe to
+work with CPAN.pm: http://community.opscode.com/cookbooks/cpan.
+
+
+=cut