Maybe your Perl can't locate your shell (cmd.exe), which is needed in order to run dir. I get the exact behaviour you descibe when I unset my PATH.

For example, 

#! c:\perl\bin\perl.exe
use CGI qw(:standard :html3);
use CGI::Carp qw(fatalsToBrowser);

print header();

print '<html><body>';

$tmp = `dir`;
if (defined($tmp)) {
   print "Dir: $tmp";
} else {
   print "Error: $!";
}

print '</body></html>';

[download]

outputs 

Error: Bad file descriptor

[download]

when my PATH is unset.

If you're really trying to get a dir listing, it would be much more efficent to use glob or readdir (like neilwatson suggested).

In reply to Re: backtick in perl 5.8 cgi under iis 6 by ikegami
in thread backtick in perl 5.8 cgi under iis 6 by cseelig

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