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Item6274: Cannot Steal STDERR mod_perl 5.8

Item Form Data

AppliesTo: Component: Priority: CurrentState: WaitingFor: TargetRelease ReleasedIn
Engine Sandbox Normal New   n/a  

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Reported By:
Applies To:
Current State:
Waiting For:
Target Release:
Released In:


When Running twiki on windows using mod_perl.

Mod_perl version:
Embedded Perl version v5.8.8 for Apache/2.0.59 (Win32) mod_perl/2.0.3 Perl/v5.8.

Twiki version:
TWiki Release 4.3.1 (Georgetown) released on 2009-04-29

Sandbox.pm fails on line 479 when attempting to `steal` the STDERR handle.

I have read the documentation detailed at http://twiki.org/cgi-bin/view/Support/HowToFixBadFileDescriptor however this does not provide a fix for my variation of the error.

The error appears to be caused by the redirection of STDERR when running in mod_perl, I have attached a solution based on that described in the mod_perl cookbook.

The solution works by creating a code block then overriding STDERR within the block (using local) where the command is executed, once the code leaves the block STDERR reverts to the previous version.

This method is compatible with mod_perl and is a much better multi-process solution.

Please find attached, the original Sandbox.pm, the fixed Sandbox.pm and a patch.

Summary Cannot Steal STDERR mod_perl 5.8
ReportedBy TWiki:Main.JamesAustin
Codebase 4.3.1
SVN Range TWiki-5.0.0, Sat, 18 Apr 2009, build 18024
AppliesTo Engine
Component Sandbox
Priority Normal
CurrentState New


TargetRelease n/a

Topic attachments
I Attachment History Action Size Date Who Comment
Perl source code filepm Sandbox.orig.pm r1 manage 16.4 K 2009-06-06 - 02:18 UnknownUser Original Sandbox.pm
Unknown file formatpatch Sandbox.patch r1 manage 1.1 K 2009-06-06 - 02:18 UnknownUser Sandbox.pm Patch
Perl source code filepm Sandbox.pm r1 manage 16.3 K 2009-06-06 - 02:19 UnknownUser Fixed Sandbox.pm
Topic revision: r1 - 2009-06-06 - JamesAustin
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