Note that the pattern eval { ... }; if ($@) { ... } suffers from issues, and this pattern is better: eval { ...; 1 } or { ... }; - or just use a module like Try::Tiny.

Other than the scoping issue of @file_list that hippo pointed out, I'm not sure I understand what problems you're having. I tried the following code on Linux and it times out the ls just fine:

use warnings;
use strict;
use Data::Dumper;

my @file_list;
eval {
    local $SIG{ALRM} = sub { die "alarm\n" }; 
    alarm 5;
    chomp( @file_list = `sleep 10; ls /tmp` );
    die "ls: \$?=$?" if $?;
    alarm 0;
1 } or do {
    die $@ unless $@ eq "alarm\n";
    warn "Timed out";
};

print Dumper(\@file_list);

[download]

Also, have a look at IPC::Run, it has timeout support, and support for several more powerful features. Here's an example that also shows Try::Tiny:

use warnings;
use strict;
use Data::Dumper;
use IPC::Run qw/ run timeout /;
use Try::Tiny;

my @file_list;
try {
    run ['ls','/tmp'], \undef, \my $lines, timeout(5)
        or die "ls: \$?=$?";
    @file_list = split /\n/, $lines;
}
catch {
    die $_ unless /^IPC::Run: timeout/;
    warn "Timed out";
};

print Dumper(\@file_list);

[download]

In reply to Re: how to stop command by haukex
in thread how to stop command by dideod.yang

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.