in reply to Need Function for Timing out shell commands

I gather from eyepopslikeamosquito's post that a pure-Perl solution that both kills the process on timeout and captures its exit status otherwise is non-trivial.

Not sure what O/S you are using. In Unix/Linux, I would be surprised to find any networking command that doesn't have a timeout option, so I would check that first. Alternatively, there is the timeout command, which would solve your problem entirely.

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  • Comment on Re: Need Function for Timing out shell commands

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Re^2: Need Function for Timing out shell commands
by salva (Canon) on Sep 15, 2011 at 08:07 UTC
    I gather from eyepopslikeamosquito's post that a pure-Perl solution that both kills the process on timeout and captures its exit status otherwise is non-trivial.

    It is not trivial, but is is not so complex either: 

    # untested!
use POSIX qw(WNOHANG _exit);
use Errno qw(ECHILD);

local $SIG{CHLD} = sub {}; # this do-nothing sub ends the
                           # select below on SIGCHLD

my $pid = fork;
if (!$pid) {
    defined $pid or die "fork failed: $!";
    do { exec @cmd }; # warnings friendly!
    _exit(1);
}

my $start = time;
while (1) {
  my $rc = waitpid ($pid, WNOHANG);
  last if $rc == $pid;
  last if $rc < 0 and $! == ECHILD;
  select (undef, undef, undef, 1);
  kill INT => $pid if time > $start + $timeout;
}

    [download]

    Using AnyEvent it would be even easier.

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