backtick in perl 5.8 cgi under iis 6

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

This code, when run as a cgi script (demo.pl, eg), does not perform the "dir"
(or does not return data to the $tmp variable, in any event).

It works in all other respects (I get a page in the browser that displays "Dir:")

Thoughts? Thanks!!

#! 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 "<p>";
print "Path is $ENV{'PATH'}";

print '</body></html>';
[download]

Here's the PATH at runtime:

Path is d:\bin\;D:\oracle\ora81\bin;C:\Program Files\Oracle\jre\1.1.7\
+bin;C:\Perl\bin\;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\W
+bem
[download]

Comment on backtick in perl 5.8 cgi under iis 6 Select or Download Code

Replies are listed 'Best First'.
Re: backtick in perl 5.8 cgi under iis 6 by ikegami (Patriarch) on Feb 16, 2006 at 21:30 UTC
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`. Read more... Example (806 Bytes) If you're really trying to get a dir listing, it would be much more efficent to use `glob` or `readdir` (like neilwatson suggested).	[reply] [d/l] [select]
Re^2: backtick in perl 5.8 cgi under iis 6 by cseelig (Initiate) on Feb 16, 2006 at 22:05 UTC
Agree. I used "dir" only to avoid getting tangled in the details of the real problem.	[reply]
Re: backtick in perl 5.8 cgi under iis 6 by neilwatson (Priest) on Feb 16, 2006 at 21:10 UTC
Use the function `readdir` instead of backticks. See `perldoc -f readdir`. Neil Watson watson-wilson.ca	[reply] [d/l] [select]
Re^2: backtick in perl 5.8 cgi under iis 6 by cseelig (Initiate) on Feb 16, 2006 at 22:13 UTC
Hi. Actually, "dir" is a stand-in for the real external job. The problem is that I can't get *anything* to work with backticks in cgi.	[reply]
Re^3: backtick in perl 5.8 cgi under iis 6 by neilwatson (Priest) on Feb 17, 2006 at 14:15 UTC
I think you are missing the point. You should never need backticks. They are a security risk. Why don't you tell us exactly what you are trying to do? Neil Watson watson-wilson.ca	[reply]
Re^4: backtick in perl 5.8 cgi under iis 6 by ikegami (Patriarch) on Feb 17, 2006 at 16:42 UTC
Re^4: backtick in perl 5.8 cgi under iis 6 by cseelig (Initiate) on Feb 17, 2006 at 16:23 UTC
Re^5: backtick in perl 5.8 cgi under iis 6 by marto (Cardinal) on Feb 17, 2006 at 16:55 UTC
Some notes below your chosen depth have not been shown here
Re^5: backtick in perl 5.8 cgi under iis 6 by runrig (Abbot) on Feb 17, 2006 at 16:45 UTC
Re: backtick in perl 5.8 cgi under iis 6 by mab (Acolyte) on Apr 26, 2006 at 03:33 UTC
I've been battling with this as well. I found that my problem was that the IIS user did not have read and execute permissions on the directory containing the programs I was trying to backtick execute. Here's my test program: #!c:\Tools\perl\5.6.1\bin\MSWin32-x86\perl.exe use CGI qw/:standard/; $ENV{PATH} = "C:\\httpdocs;"; $\| = 1; print header; print `dir`; [download] Inside of C:\httpdocs, I put a copy of cmd.exe. On the C:\httpdocs directory, I gave the IIS user "read & execute," "list folder contents" and "read" permissions. After that, the test started working. Good luck, Mike P.S. If your scripts write to a file, be sure the IIS user has write permissions on the target directory.	[reply] [d/l]