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diff --git a/Master/tlpkg/tlperl/lib/Net/libnetFAQ.pod b/Master/tlpkg/tlperl/lib/Net/libnetFAQ.pod deleted file mode 100644 index e6ec362f36a..00000000000 --- a/Master/tlpkg/tlperl/lib/Net/libnetFAQ.pod +++ /dev/null @@ -1,303 +0,0 @@ -=head1 NAME - -libnetFAQ - libnet Frequently Asked Questions - -=head1 DESCRIPTION - -=head2 Where to get this document - -This document is distributed with the libnet distribution, and is also -available on the libnet web page at - - http://search.cpan.org/~gbarr/libnet/ - -=head2 How to contribute to this document - -You may mail corrections, additions, and suggestions to me -gbarr@pobox.com. - -=head1 Author and Copyright Information - -Copyright (c) 1997-1998 Graham Barr. All rights reserved. -This document is free; you can redistribute it and/or modify it -under the terms of the Artistic License. - -=head2 Disclaimer - -This information is offered in good faith and in the hope that it may -be of use, but is not guaranteed to be correct, up to date, or suitable -for any particular purpose whatsoever. The authors accept no liability -in respect of this information or its use. - - -=head1 Obtaining and installing libnet - -=head2 What is libnet ? - -libnet is a collection of perl5 modules which all related to network -programming. The majority of the modules available provided the -client side of popular server-client protocols that are used in -the internet community. - -=head2 Which version of perl do I need ? - -libnet has been know to work with versions of perl from 5.002 onwards. However -if your release of perl is prior to perl5.004 then you will need to -obtain and install the IO distribution from CPAN. If you have perl5.004 -or later then you will have the IO modules in your installation already, -but CPAN may contain updates. - -=head2 What other modules do I need ? - -The only modules you will need installed are the modules from the IO -distribution. If you have perl5.004 or later you will already have -these modules. - -=head2 What machines support libnet ? - -libnet itself is an entirely perl-code distribution so it should work -on any machine that perl runs on. However IO may not work -with some machines and earlier releases of perl. But this -should not be the case with perl version 5.004 or later. - -=head2 Where can I get the latest libnet release - -The latest libnet release is always on CPAN, you will find it -in - - http://www.cpan.org/modules/by-module/Net/ - -The latest release and information is also available on the libnet web page -at - - http://search.cpan.org/~gbarr/libnet/ - -=head1 Using Net::FTP - -=head2 How do I download files from an FTP server ? - -An example taken from an article posted to comp.lang.perl.misc - - #!/your/path/to/perl - - # a module making life easier - - use Net::FTP; - - # for debugging: $ftp = Net::FTP->new('site','Debug',10); - # open a connection and log in! - - $ftp = Net::FTP->new('target_site.somewhere.xxx'); - $ftp->login('username','password'); - - # set transfer mode to binary - - $ftp->binary(); - - # change the directory on the ftp site - - $ftp->cwd('/some/path/to/somewhere/'); - - foreach $name ('file1', 'file2', 'file3') { - - # get's arguments are in the following order: - # ftp server's filename - # filename to save the transfer to on the local machine - # can be simply used as get($name) if you want the same name - - $ftp->get($name,$name); - } - - # ftp done! - - $ftp->quit; - -=head2 How do I transfer files in binary mode ? - -To transfer files without <LF><CR> translation Net::FTP provides -the C<binary> method - - $ftp->binary; - -=head2 How can I get the size of a file on a remote FTP server ? - -=head2 How can I get the modification time of a file on a remote FTP server ? - -=head2 How can I change the permissions of a file on a remote server ? - -The FTP protocol does not have a command for changing the permissions -of a file on the remote server. But some ftp servers may allow a chmod -command to be issued via a SITE command, eg - - $ftp->quot('site chmod 0777',$filename); - -But this is not guaranteed to work. - -=head2 Can I do a reget operation like the ftp command ? - -=head2 How do I get a directory listing from an FTP server ? - -=head2 Changing directory to "" does not fail ? - -Passing an argument of "" to ->cwd() has the same affect of calling ->cwd() -without any arguments. Turn on Debug (I<See below>) and you will see what is -happening - - $ftp = Net::FTP->new($host, Debug => 1); - $ftp->login; - $ftp->cwd(""); - -gives - - Net::FTP=GLOB(0x82196d8)>>> CWD / - Net::FTP=GLOB(0x82196d8)<<< 250 CWD command successful. - -=head2 I am behind a SOCKS firewall, but the Firewall option does not work ? - -The Firewall option is only for support of one type of firewall. The type -supported is an ftp proxy. - -To use Net::FTP, or any other module in the libnet distribution, -through a SOCKS firewall you must create a socks-ified perl executable -by compiling perl with the socks library. - -=head2 I am behind an FTP proxy firewall, but cannot access machines outside ? - -Net::FTP implements the most popular ftp proxy firewall approach. The scheme -implemented is that where you log in to the firewall with C<user@hostname> - -I have heard of one other type of firewall which requires a login to the -firewall with an account, then a second login with C<user@hostname>. You can -still use Net::FTP to traverse these firewalls, but a more manual approach -must be taken, eg - - $ftp = Net::FTP->new($firewall) or die $@; - $ftp->login($firewall_user, $firewall_passwd) or die $ftp->message; - $ftp->login($ext_user . '@' . $ext_host, $ext_passwd) or die $ftp->message. - -=head2 My ftp proxy firewall does not listen on port 21 - -FTP servers usually listen on the same port number, port 21, as any other -FTP server. But there is no reason why this has to be the case. - -If you pass a port number to Net::FTP then it assumes this is the port -number of the final destination. By default Net::FTP will always try -to connect to the firewall on port 21. - -Net::FTP uses IO::Socket to open the connection and IO::Socket allows -the port number to be specified as part of the hostname. So this problem -can be resolved by either passing a Firewall option like C<"hostname:1234"> -or by setting the C<ftp_firewall> option in Net::Config to be a string -in in the same form. - -=head2 Is it possible to change the file permissions of a file on an FTP server ? - -The answer to this is "maybe". The FTP protocol does not specify a command to change -file permissions on a remote host. However many servers do allow you to run the -chmod command via the C<SITE> command. This can be done with - - $ftp->site('chmod','0775',$file); - -=head2 I have seen scripts call a method message, but cannot find it documented ? - -Net::FTP, like several other packages in libnet, inherits from Net::Cmd, so -all the methods described in Net::Cmd are also available on Net::FTP -objects. - -=head2 Why does Net::FTP not implement mput and mget methods - -The quick answer is because they are easy to implement yourself. The long -answer is that to write these in such a way that multiple platforms are -supported correctly would just require too much code. Below are -some examples how you can implement these yourself. - -sub mput { - my($ftp,$pattern) = @_; - foreach my $file (glob($pattern)) { - $ftp->put($file) or warn $ftp->message; - } -} - -sub mget { - my($ftp,$pattern) = @_; - foreach my $file ($ftp->ls($pattern)) { - $ftp->get($file) or warn $ftp->message; - } -} - - -=head1 Using Net::SMTP - -=head2 Why can't the part of an Email address after the @ be used as the hostname ? - -The part of an Email address which follows the @ is not necessarily a hostname, -it is a mail domain. To find the name of a host to connect for a mail domain -you need to do a DNS MX lookup - -=head2 Why does Net::SMTP not do DNS MX lookups ? - -Net::SMTP implements the SMTP protocol. The DNS MX lookup is not part -of this protocol. - -=head2 The verify method always returns true ? - -Well it may seem that way, but it does not. The verify method returns true -if the command succeeded. If you pass verify an address which the -server would normally have to forward to another machine, the command -will succeed with something like - - 252 Couldn't verify <someone@there> but will attempt delivery anyway - -This command will fail only if you pass it an address in a domain -the server directly delivers for, and that address does not exist. - -=head1 Debugging scripts - -=head2 How can I debug my scripts that use Net::* modules ? - -Most of the libnet client classes allow options to be passed to the -constructor, in most cases one option is called C<Debug>. Passing -this option with a non-zero value will turn on a protocol trace, which -will be sent to STDERR. This trace can be useful to see what commands -are being sent to the remote server and what responses are being -received back. - - #!/your/path/to/perl - - use Net::FTP; - - my $ftp = new Net::FTP($host, Debug => 1); - $ftp->login('gbarr','password'); - $ftp->quit; - -this script would output something like - - Net::FTP: Net::FTP(2.22) - Net::FTP: Exporter - Net::FTP: Net::Cmd(2.0801) - Net::FTP: IO::Socket::INET - Net::FTP: IO::Socket(1.1603) - Net::FTP: IO::Handle(1.1504) - - Net::FTP=GLOB(0x8152974)<<< 220 imagine FTP server (Version wu-2.4(5) Tue Jul 29 11:17:18 CDT 1997) ready. - Net::FTP=GLOB(0x8152974)>>> user gbarr - Net::FTP=GLOB(0x8152974)<<< 331 Password required for gbarr. - Net::FTP=GLOB(0x8152974)>>> PASS .... - Net::FTP=GLOB(0x8152974)<<< 230 User gbarr logged in. Access restrictions apply. - Net::FTP=GLOB(0x8152974)>>> QUIT - Net::FTP=GLOB(0x8152974)<<< 221 Goodbye. - -The first few lines tell you the modules that Net::FTP uses and their versions, -this is useful data to me when a user reports a bug. The last seven lines -show the communication with the server. Each line has three parts. The first -part is the object itself, this is useful for separating the output -if you are using multiple objects. The second part is either C<<<<<> to -show data coming from the server or C<>>>>> to show data -going to the server. The remainder of the line is the command -being sent or response being received. - -=head1 AUTHOR AND COPYRIGHT - -Copyright (c) 1997 Graham Barr. -All rights reserved. - |