Problems with Net::FTP

haps has asked for the wisdom of the Perl Monks concerning the following question:

Hello Monks, I am new to perl and I am converting my old shell scripts over as a method of learning. I am having trouble with one script that I use to download packages that I require via ftp. Some files that I try to download end up a few bytes short. My script is:

#!/usr/bin/perl

my $host = 'ftp.iinet.net.au';
my $arch = 'i386';
my $ver  = '4.3';

use Net::FTP;
my $package = shift;

my $ftp = Net::FTP->new($host, debug => 0) or die "Cant connect: $@";
$ftp->binary();

$ftp->login("anonymous", "-anonymous@") or die "Cant login: ", $ftp->m
+essage;
$ftp->cwd("pub/OpenBSD/$ver/packages/$arch") or die "Cant change dir: 
+", $ftp->message;

my @pkglist = $ftp->ls or die "Cant get dir listing: ", $ftp->message;

for( @pkglist ) {

    my $pkg = $_;

    unless( $pkg =~ $package ) { next; }

    $pkg =~ s/\S\s{7}?//;

    my $test = promptUser( "Download package?", "y" );

    if( $test eq "y" ) {
        $ftp->get( $pkg ) or die "Cannot retrieve matching package: ",
+ $ftp->message;
    }

}

sub promptUser {

    local( $promptString, $defaultValue ) = @_;

    if ( $defaultValue ) {
    print $promptString, "[", $defaultValue, "]: ";
    } else {
    print $promptString, ": ";
    }

    $| = 1;
    $_ = <STDIN>;

    chomp;

    if ("$defaultValue") {
    return $_ ? $_ : $defaultValue;
    } else {
    return $_;
    }
}

exit;
[download]

Comment on Problems with Net::FTP Download Code

Replies are listed 'Best First'.
Re: Problems with Net::FTP by zentara (Cardinal) on Jan 05, 2009 at 16:14 UTC
If you are missing a few bytes, you might try binary mode `if( $test eq "y" ) { # search for binary in perldoc Net::FTP $ftp->binary(); $ftp->get( $pkg ) or die "Cannot retrieve matching package: ",` [download] I'm not really a human, but I play one on earth Remember How Lucky You Are	[reply] [d/l]
Re^2: Problems with Net::FTP by haps (Novice) on Jan 05, 2009 at 16:26 UTC
I was turning on binary mode straight after the call to Net::FTP->new(), but moving it inside the test, as in your reply, has indeed solved the issue. Thankyou very much for your help. :D	[reply]
Re: Problems with Net::FTP by eye (Chaplain) on Jan 06, 2009 at 07:18 UTC
The "binary" call generates an instruction to the remote host to disable line ending translation. You cannot alter the state of the "ftp connection" until you authenticate. Hence, you need to put the "binary" call after the login, but it should not be necessary to put it inside the loop.	[reply]
Re^2: Problems with Net::FTP by haps (Novice) on Jan 07, 2009 at 00:49 UTC
You are quite correct that it not necessary to have it inside the loop. I actually figured this out myself after looking at the code again and realizing that the reason it would not work originally was because I was not connected and authenticated. So I now have the script turn on binary mode after loggin in.	[reply]