Bug with Backticks under Win32?

strat has asked for the wisdom of the Perl Monks concerning the following question:

Hello,

when I execute the following code under WinXP, there are strange results:

01 #! /usr/bin/perl
02: use warnings;
03: use strict;
04: 
05: my @result = `dir`; # as list
06: die "Error 1: $!\n" if $!;
07: print @result, "\n\n";
08: 
09: my $result = `dir`;
10: die "Error 2: $!\n" if $!; 
11: print $result;
[download]

Well, the whole code runs fine under 5.8.5 under linux or cygwin/WinXP, but with ActivestatePerl 809 and 810 under WinXP I get an error for the second backtick-command whereas the first runs fine:

Error 2: Bad file descriptor
[download]

Is this a bug? or am I the bug?

Best regards,
perl -e "s>>*F>e=>y)\*martinF)stronat)=>print,print v8.8.8.32.11.32"

Comment on Bug with Backticks under Win32? Select or Download Code

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Re: Bug with Backticks under Win32? by ikegami (Patriarch) on Nov 25, 2004 at 21:05 UTC
To quote perlvar: You shouldn't depend on the value of $! to be anything in particular unless you've gotten a specific error return indicating a system error. `` is not a system call (it's an operator), and the documentation of the operator doesn't mention `$!`. You haven't been told there was an error (much less a system error) before checking `$!`. Therefore, it's a bug to check `$!`. Other functions (such as `open(FILE, '...\|')`) provide more feedback on errors.	[reply] [d/l] [select]
Re: Bug with Backticks under Win32? by tachyon (Chancellor) on Nov 25, 2004 at 22:09 UTC
As noted you should not be checking $! as it is meaningless in this context. FWIW on Win2K Perl 5.6.2 it dies on the first call with `Error 1: No such file or directory.` With the 'error' checks commented out it works as expected and prints the dir listings.</code> cheers tachyon	[reply] [d/l]