system() command with a time limit

I want to use system() (or `command`) to run an external
command from
my Perl script. However, if the external command takes more
than 30
seconds (for example) to run, I want to kill it, and move on
with the
rest of my Perl script. How do I do this?

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>>>>> "Kelly" == Kelly Jones
<kelly.terry.jonesgmail.com> writes:

Kelly> I want to use system() (or `command`) to run an
external command from
Kelly> my Perl script. However, if the external command
takes more than 30
Kelly> seconds (for example) to run, I want to kill it,
and move on with the
Kelly> rest of my Perl script. How do I do this?

You'll have to manage the forking yourself, and then have
the parent
kill the child if it doesn't finish within your time.

Something like:

my $result = eval {
  my $kidpid = open my $kidhandle, "-|";
  defined $kidpid or die "Cannot fork: $!";
  if ($kidpid) { # I am the parent:
    alarm(30);
    local $ARGV = sub {
      kill 15, $kidpid;
      waitpid $kidpid;
      die "timeout";
    };
    my $buf;
    $buf .= $_ while <$kidhandle>;
    alarm(0);
    $buf;
  } else { # I am the kid:
    exec "whatever", "command",
"you", "want";
    die "Cannot find whatever: $!";
  }
}; die $ unless $ =~ /timeout/;

That's untested, but probably pretty close.

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