Re^2: Timing out backquoted executions

Thanks guys. Now I'm noticing though that when I do this, the process continues running. How can I be sure to terminate this process?

> cat perl.pl
#!/usr/bin/perl

eval {
  $SIG{ALRM} = sub { die "Timed out\n"; };
  alarm(5);
  `perl -e 'while(1){sleep 1;}'`;
  alarm(0);
};
print "Died with: $@\n";

> ./perl.pl
Died with: Timed out

> ps
  PID TTY          TIME CMD
11551 pts/0    00:00:00 bash
11648 pts/0    00:00:00 perl
11651 pts/0    00:00:00 ps
[download]

Comment on Re^2: Timing out backquoted executions Download Code

Replies are listed 'Best First'.
Re^3: Timing out backquoted executions by Joost (Canon) on Aug 02, 2007 at 20:19 UTC
You're probably better off using piped open (see perlopentut) in this case, since that will give you the process id of the spawned process: `# set up alarm... my $pid; $SIG{ALRM} = sub { kill $pid; die "Timed out" }; alarm(5); $pid = open PROG,"/some program\|" or die "Can't fork: $!"; my $input = join('',<PROG>); alarm(0); close PROG;` [download] Note; code is untested. update: added alarm() calls. "What should it profit a man, if he should win a flame war, yet lose his cool?"	[reply] [d/l]

Replies are listed 'Best First'.

Re^3: Timing out backquoted executions
by Joost (Canon) on Aug 02, 2007 at 20:19 UTC

perlopentut

# set up alarm...
my $pid;
$SIG{ALRM} = sub { kill $pid; die "Timed out" };
alarm(5);
$pid = open PROG,"/some program|" or die "Can't fork: $!";
my $input = join('',<PROG>);
alarm(0);
close PROG;
[download]

update: added alarm() calls.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

[reply]
[d/l]