Hi Guys, I'm trying to 'safely' execute a shell command passed to a function (exec_safe). My intention is to return the output of the shell command and the exit code if the command completes. exec_safe receives the following: $_[0] = Command to be run. This may contain pipes, redirects, etc. $_1 = The timeout (seconds) for the command $_2 = A nice value that the command is run at. After some googling, etc I've come up with the following (Comments included): 
sub exec_safe {
    my @cmd; # Return variable
    eval {
        local $SIG{ALRM} = sub { die "Timeout\n" };
        alarm $_[1];
        @cmd = `nice -n $_[2] $_[0]`;
        alarm 0;
    };
    if($@) { # If command fails, return non-zero and msg
        return ("Command timeout",1);
    } else {
        chomp @cmd; push(@cmd,$? >> 8);
        return @cmd;
    }
}

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While this operates correctly in allowing the perl program to continue after the timeout, in testing it's not terminating the spawned process. For example, if I call 'sleep 250' with a timeout of 10, the function will return after 10 seconds with "Command Timeout",1, however PS shows that the process 'sleep 250' is still running. Caveat: Note that because I'm looking for the returned data and exit code of the child process, exec_safe cannot return until it's finished or timed out. From a brief googlin', it doesn't appear that fork will allow me to get all the data I need. Any ideas?

In reply to Execute shell command, grab it's return, terminate on timeout by Haioken

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