diff options
author | Norbert Preining <preining@logic.at> | 2010-05-12 16:54:37 +0000 |
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committer | Norbert Preining <preining@logic.at> | 2010-05-12 16:54:37 +0000 |
commit | 661c41a09e39a182865e0b51e34cc995a0dc96e8 (patch) | |
tree | 2f79bb1406e22fdcb2587be8ffda6c0c609d7932 /Master/tlpkg/tlperl/lib/SDBM_File.pm | |
parent | b645030efc22e13c2498a1522083634ab91b2de1 (diff) |
move tlperl.straw to tlperl
git-svn-id: svn://tug.org/texlive/trunk@18210 c570f23f-e606-0410-a88d-b1316a301751
Diffstat (limited to 'Master/tlpkg/tlperl/lib/SDBM_File.pm')
-rwxr-xr-x | Master/tlpkg/tlperl/lib/SDBM_File.pm | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/Master/tlpkg/tlperl/lib/SDBM_File.pm b/Master/tlpkg/tlperl/lib/SDBM_File.pm new file mode 100755 index 00000000000..d1209e0158b --- /dev/null +++ b/Master/tlpkg/tlperl/lib/SDBM_File.pm @@ -0,0 +1,116 @@ +package SDBM_File; + +use strict; +use warnings; + +require Tie::Hash; +use XSLoader (); + +our @ISA = qw(Tie::Hash); +our $VERSION = "1.06"; + +XSLoader::load 'SDBM_File', $VERSION; + +1; + +__END__ + +=head1 NAME + +SDBM_File - Tied access to sdbm files + +=head1 SYNOPSIS + + use Fcntl; # For O_RDWR, O_CREAT, etc. + use SDBM_File; + + tie(%h, 'SDBM_File', 'filename', O_RDWR|O_CREAT, 0666) + or die "Couldn't tie SDBM file 'filename': $!; aborting"; + + # Now read and change the hash + $h{newkey} = newvalue; + print $h{oldkey}; + ... + + untie %h; + +=head1 DESCRIPTION + +C<SDBM_File> establishes a connection between a Perl hash variable and +a file in SDBM_File format;. You can manipulate the data in the file +just as if it were in a Perl hash, but when your program exits, the +data will remain in the file, to be used the next time your program +runs. + +Use C<SDBM_File> with the Perl built-in C<tie> function to establish +the connection between the variable and the file. The arguments to +C<tie> should be: + +=over 4 + +=item 1. + +The hash variable you want to tie. + +=item 2. + +The string C<"SDBM_File">. (Ths tells Perl to use the C<SDBM_File> +package to perform the functions of the hash.) + +=item 3. + +The name of the file you want to tie to the hash. + +=item 4. + +Flags. Use one of: + +=over 2 + +=item C<O_RDONLY> + +Read-only access to the data in the file. + +=item C<O_WRONLY> + +Write-only access to the data in the file. + +=item C<O_RDWR> + +Both read and write access. + +=back + +If you want to create the file if it does not exist, add C<O_CREAT> to +any of these, as in the example. If you omit C<O_CREAT> and the file +does not already exist, the C<tie> call will fail. + +=item 5. + +The default permissions to use if a new file is created. The actual +permissions will be modified by the user's umask, so you should +probably use 0666 here. (See L<perlfunc/umask>.) + +=back + +=head1 DIAGNOSTICS + +On failure, the C<tie> call returns an undefined value and probably +sets C<$!> to contain the reason the file could not be tied. + +=head2 C<sdbm store returned -1, errno 22, key "..." at ...> + +This warning is emitted when you try to store a key or a value that +is too long. It means that the change was not recorded in the +database. See BUGS AND WARNINGS below. + +=head1 BUGS AND WARNINGS + +There are a number of limits on the size of the data that you can +store in the SDBM file. The most important is that the length of a +key, plus the length of its associated value, may not exceed 1008 +bytes. + +See L<perlfunc/tie>, L<perldbmfilter>, L<Fcntl> + +=cut |