Re: "No child processes" problem with fork() call

your error message looks like a system error. Has your OS changed/upgraded? Fork processes limits changed? Are you sure the spawned (extenral) process does what it used to do? Perhaps No child processes - system limit? can help?

Also: your script upon entry forks. Perhaps print something when it enters/forks to count how many forks=children you have (edit: and print something when child exits/returns to offset), perhaps this is a problem caused by a sow-happy driver script.

Comment on Re: "No child processes" problem with fork() call

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Re^2: "No child processes" problem with fork() call by bliako (Abbot) on Jul 13, 2019 at 13:38 UTC
Re: No child processes - system limit? shows a way to recreate the problem which it attributes to: Normally, you'd get this error (ECHILD) if you wait for a child, but there is no child Also, from the source of IPC::System::Simple (sub `capturex()` called by `capture()`): `# This next line also does an implicit fork. my $pid = open(my $pipe, '-\|'); ## no critic if (not defined $pid) { croak sprintf(FAIL_START, $command, $!); } elsif (not $pid) { # Child process, execs command.` [download] So there is an implicit fork there expectedly. Additional to all your other forks. So I would follow dave_the_m's suggestion Re: "No child processes" problem with fork() call and check if `fork()` does succeed before `wait`ing for that child. `fork()` may fail when a maximum number of children has been reached according to the OS.	[reply] [d/l] [select]

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Re^2: "No child processes" problem with fork() call
by bliako (Abbot) on Jul 13, 2019 at 13:38 UTC

Re: No child processes - system limit? shows a way to recreate the problem which it attributes to: Normally, you'd get this error (ECHILD) if you wait for a child, but there is no child

Also, from the source of IPC::System::Simple (sub capturex() called by capture()):

        # This next line also does an implicit fork.
        my $pid = open(my $pipe, '-|');  ## no critic
 
        if (not defined $pid) {
                croak sprintf(FAIL_START, $command, $!);
        } elsif (not $pid) {
                # Child process, execs command.
[download]

So there is an implicit fork there expectedly. Additional to all your other forks.

So I would follow dave_the_m's suggestion Re: "No child processes" problem with fork() call and check if fork() does succeed before waiting for that child. fork() may fail when a maximum number of children has been reached according to the OS.

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