Unfortunatelly sleeping doesn't solve the problem.

I have tested all more throughly and modified program: 
#!/usr/bin/perl -w

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

[download]

Now I ran commands:
(ulimit -u100; ./my_program)
(ulimit -u50; ./my_program)
(ulimit -u20; ./my_program)

[download]

The first one hang on 95-th iteration. The second hang on 45-th iteration. The third one hang on 15-th iteration. So wen you set maximum number or processes to N (ulimit -u<N>), then program hangs on N-5 iteration.
I want that program to fail (return nonzero code) when no processes are available...

In reply to Re^2: Ulimit makes program hang by memo2005
in thread Ulimit makes program hang by memo2005

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