in reply to Read part of a file over FTP

This uses Net::FTP to fetch the first two hundred bytes of a 180k file:

#! perl -slw
use strict;
use Net::FTP;

my $ftp = Net::FTP->new( 'ftp.software.ibm.com' );
$ftp->login( 'anonymous', 'anonymous@' );
$ftp->cwd( '/ftp' );
$ftp->ascii;

my $xfr = $ftp->retr( '00_Catalog' );

my $buf;
$xfr->read( $buf, 200 );

print $buf;

[download]
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

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Re^2: Read part of a file over FTP
by ronin78 (Novice) on May 27, 2011 at 19:29 UTC

    Yes, this is what I wanted! Thanks very much!

    As a follow up question, the buffer now returns the first file in my loop, and I get the text that I want, but fails on the second with the error: Can't call method "read" on an undefined value. However, I have verified that the new filename is correct, so I assume that there must be some problem with reinitializing the dataconn object?

    Is there a recommended way to clear a retr() so that a new one can be called? Or is that not even likely to be my problem?

    Relevant code is below: The while loop is on a MySQL query return. Note that I haven't done anything with the buffer yet. 
    while (@results = $filequery->fetchrow()) {
            $filename="/".$filename;
            print "$filename\n";
            $xfr = $ftp->retr($filename);
            $xfr->read($header,1400);
            print "$header\n";
        }

    [download]
[reply]
[d/l]
      Note, for the above code, that I have tried the following things to close the retr(): 
      $ftp->close();
$xfr->close();

      [download]
      But no joy. I'm just stabbing in the dark, though, so that's not really surprising.
[reply]
[d/l]

        Use $xfr->abort; to abort the retr, and $ftp->quit to close the connection.

        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority".
        In the absence of evidence, opinion is indistinguishable from prejudice.
[reply]
[d/l]
[select]
        Fantastic! Sorry if my questions are noobish, and thanks very much for the help.

        Matt

[reply]

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