Article 9028 of comp.lang.perl:

Article 9028 of comp.lang.perl:
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From: Tom Christiansen <[email protected]>
Subject: Re: How to close an unknown descriptor from a perl script
Message-ID: <[email protected]>
Originator: [email protected]
Sender: [email protected] (USENET News System)
Reply-To: [email protected] (Tom Christiansen)
Organization: University of Colorado, Boulder
References: <[email protected]>
Date: Sun, 19 Dec 1993 16:43:25 GMT
Lines: 34

:-> In comp.lang.perl, [email protected] writes:
: I figure the only way this could be happening is if a descriptor
:to the client is inadvertently kept open by httpd and passed to the
:perl script. So how can the perl script guarantee that it has closed
:ALL descriptors. A C program could just call close on descriptors
:0 to n where n is big enough and ignore all errors on non-opened
:descriptors.

Probably the easiest way is

require 'syscall.ph';
for ($fd = 3; $fd < 200; $fd++) {
syscall(&SYS_close, $fd);
}

But if your C library doesn't support syscall(), you'll have to do it
differently. I'll assume that you aren't putting file handles into
other packages:

foreach $symname ( keys %_main ) {
next unless defined fileno($symname);
next if $symname =~ /^STD(IN|OUT|ERR)$/;
close($symname);
}

You might also look into $^F.

--tom

--
Tom Christiansen [email protected]
"Will Hack Perl for Fine Food and Fun"
Boulder Colorado 303-444-3212