Re: Strange Behaviour with Backticks

Did you over-simplify the matter? Are the parameters really 'A' and 'B' ? or are they something else? What binary are you running? Does it switch filehandles based on input? It's hard to tell.

For debugging, that varies (by platform). First, check what's in $?, maybe your binary just dies. On linux, I'd run the perl script with strace -f -ff -o outputfile script.pl. For solaris, there's truss, ktrace on *BSD. Oh, and then - "use the source, luke" - if you have them, that is ;-)

--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}

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Re^2: Strange Behaviour with Backticks by neversaint (Deacon) on Jul 21, 2006 at 14:47 UTC
Dear shmem, Did you over-simplify the matter? Well, actually it runs under a CGI script (See the code in my reply to Fletch below). I hope this doesn't make the difference... Are the parameters really 'A' and 'B' ? or are they something else? They consist of two characters ('AB','CD'). What binary are you running? They are C binary. Does it switch filehandles based on input? It's hard to tell. Not so sure. How can I check that? --- neversaint and everlastingly indebted.......	[reply] [d/l]
Re^3: Strange Behaviour with Backticks by shmem (Chancellor) on Jul 21, 2006 at 16:18 UTC
Hello neversaint, I hope this doesn't make the difference... Well, it must not, but it could, as fletch notes below. Running under apache there's no tty. Environment is different. If under `chroot`, even more. Search paths could be different. UID/GID, etc. They consist of two characters ('AB','CD'). Literally `AB` and `CD` What are these for? Floppy disk and hard disk labels? They are C binary. And what is it supposed to do? You scarce informations leave me to just guessing :-/ Not so sure. How can I check that? As i told you. What OS are you running? If Linux, `strace(1)` the binary. You should see `access()`, `open()` and `ioctl()` calls. If they involve a tty when run with `AB`, but not when run with `CD`, there you have it. If running on some *BSD, `ktrace(1)` it and `kdump(1)` the output. If Solaris, use `truss`. If Windows, grab some stuff from Sysinternals^WMicrosoft. Do you have the source for the binary? a man page? any documentation? What's it's real name, anyways? --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---222---------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l] [select]