AFAIK grep -m 1 exiting causes the OS to send a SIGPIPE to tac upon grep exit... hmm. Could it be that SIGPIPE is masked somewhere in mod_perl, ? is that masking propagated to the child? Is it even possible to mask a signal for a process group? Now that's something I don't know, you got me there :-)

If that's the case - i.e. if SIGPIPE is masked - try my solution (which doesn't involve grep) and kill off tac with another signal (15 or, if it's renitent, 9 - SIGKILL).

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^3: Emulating command line pipe by shmem
in thread Emulating command line pipe by davistv

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