After insterting sleep before shelling out I get exactly same results.

I'm not a system programmer to analyse strace output...sorry.

I have tried fork and exec this way: 
#!/usr/bin/perl -w

my $x = $ARGV[0] + 1;
print STDERR "$x\n";

if (!defined($child_pid = fork())) {
    die "cannot fork: $!";
} elsif ($child_pid) {
    waitpid($child_pid, 0);
} else {
    exec "$0 $x";
}

[download]
This program never hangs -- always says cannot fork: Resource temporarily unavailable at ./fork_wait line 7.
But I must grab output of command so I can't use this solution.

In reply to Re^4: Ulimit makes program hang by memo2005
in thread Ulimit makes program hang by memo2005

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