how to kill subprocess when it goes longer than 20 seconds?

echoangel911 has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I am launching a command like this:


   open (SYS, "/bin/tcsh $tempfilename | ") or die "$!";
   while (<SYS>)
   {
      print "[DEBUG] $_ <br>";
   }
   close SYS;
[download]

Inside the tempfilename, the environment is setup and my tool is called. If someone else is using my tool due to license restrictions, the program will hang thus causing my cgi perl script to hang. Is there anyway to put a timer on this to exit and then continue on?

Comment on how to kill subprocess when it goes longer than 20 seconds? Download Code

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Re: how to kill subprocess when it goes longer than 20 seconds? by ikegami (Patriarch) on Mar 28, 2007 at 15:17 UTC
`open` returns the child's PID on success. You can use `kill` along with this PID to end the process. That leaves you with waiting for 20 seconds. `alarm` is one way to go.	[reply] [d/l] [select]
Re^2: how to kill subprocess when it goes longer than 20 seconds? by echoangel911 (Sexton) on Mar 28, 2007 at 17:28 UTC
is this correct? `my $temppid = open (SYS, "/bin/tcsh $tempfilename \| ") or die "$!"; kill $temppid if (alarm (5)); while (<SYS>) { print "[DEBUG] $_ <br>"; } close SYS;` [download]	[reply] [d/l]
Re^3: how to kill subprocess when it goes longer than 20 seconds? by izut (Chaplain) on Mar 28, 2007 at 17:41 UTC
Check alarm documentation. There's a lot of examples how you do that. Igor 'izut' Sutton your code, your rules.	[reply]