This works for me on both Linux and Windows (Strawberry Perl). First, we set a timeout in the $time variable, which in this example is two seconds. Then, inside of an eval, we simulate a long (relatively) running command, which is wrapped by an ALRM signal handler. If the command runs longer than the timeout (in the example, I simulate a long running command with sleep), we catch the error message caught from die, and act on it. Otherwise, we display the output of the command
Reduce the sleep to a lower number than $time (ie. zero) to get the return properly:
use warnings;
use strict;
my $time = 2;
my $cmd = 'dir';
my $check = 1;
my $output;
print "check is $check\n";
eval {
local $SIG{ALRM} = sub { die 'timed out'; };
alarm $time;
$output = `$cmd`;
sleep 4;
$check++;
alarm 0;
};
if ($@ && $@ =~ /timed out/){
print "damn command timed out!\n";
}
else {
print "$output\n";
}
print "check is now $check\n";
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