Why does fork/exec not work on Win NT 4.0 Server?

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

Hi all!

I try to run "unzip" out of a cgi-script served by Apache under Win NT 4.0 Server.
The same code worked fine with another istallation on Win NT 4.0 (not Server Edition)
Now I always get the"Internal Server error" I try to run my cgi script. The perl interpreter does not say anything while running from dos box.
I checked file permissions and Apache is running as Administrator.
Help would be great!!!

Perl Version 5.005_03

my $file = "bla.zip";
my $command = "p:/tools/wni/unzip.exe $myFile";
unless (defined ($pid = fork)) {
print "No fork:$!\n";
}
unless ($pid) {
exec ($command) or print "exec $command not possible:$!";
exit;
}
waitpid ($pid, 0);

Have a good time...
Georg

wrkvg@SoftwareAG.com

Comment on Why does fork/exec not work on Win NT 4.0 Server?

Replies are listed 'Best First'.
Re: Why does fork/exec not work on Win NT 4.0 Server? by abstracts (Hermit) on Jul 23, 2001 at 22:44 UTC
Hello, A few notes about your code: In the second line, $myFile is not defined. I think you wanted to use $file. You are printing "No fork: $!\n" without first printing "Content-type: text/html\n\n"; This causes 500 Fatal Error. You are forking a process that execs to unzip a file. The main process however sits idle waitpiding for the child to exit. You should've just used system to unzip the file and return to the user. You can also use the Archive::Zip module instead of firing another process just to do the unzipping. Hope this helps,,, Aziz,,,	[reply]
Re: Why does fork/exec not work on Win NT 4.0 Server? by bikeNomad (Priest) on Jul 23, 2001 at 20:23 UTC
Try using CGI::Carp and fatalsToBrowser to find out what your problem is. But first, do you have unzip in the same place on both systems?	[reply]
Re: Re: Why does fork/exec not work on Win NT 4.0 Server? by LupoX (Pilgrim) on Jul 24, 2001 at 11:43 UTC
Hi Mr Nomad! I checkes environment and zip / unzip is in the PATH variable. This works. From command line there are no Problems. I also tried to exec the executable with full destination path. exec (c:/tools/unzip $file); which also does not work. Thanks for Your time... Georg	[reply]
(tye)Re: Why does fork/exec not work on Win NT 4.0 Server? by tye (Sage) on Jul 24, 2001 at 11:52 UTC
Win32 Perl 5.005 supports fork emulation but just barely. I found it very easy to break. abstracts is correct. In particular, use system rather than doing the fork and exec yourself; it is more portable. - tye (but my friends call me "Tye")	[reply]