Shell Programming and Scripting

I have a cgi script that calls a perl script (A.pl) to do something in backgroup, when run that perl script in command everything works fine, but when it calls by the CGI script, nothing works. I have tried another perl script (B.pl not cgi) calls A.pl, and it works fine.
The A.pl is chmod 777,

Can someone here help?

Thank you!


Here is my cgi calling A.pl:
#!/usr/bin/perl -w
#
use CGI;
$mycgi = new CGI;

print $mycgi->header;
print $mycgi->start_html(
-title=>'System Tes'',
-BGCOLOR=>'#FFFFCC');


# do something here

# system calls both don't work
system("/mypath/A.pl");

unless (system("/mypath/A.pl")) {
print "system calls failed: $!"; # not seeing this msg from browser
}


# print HTML message here, is seen from browser

print $mycgi->end_html;
exit;

What do you mean by "nothing works", do you get an error ? 5xx HTTP error perhaps? Has this ever worked? Are other cgi scripts working ok?

You should really never need to chmod 777 any script, especially a CGI script.

add this to the top of your script. I suggest using this in all of your scripts.

Code:

use strict;

Check your web server logs. The errors should be logged there. This is the first place you should look.

If possible, you can rewrite your program to include code from A.pl

Check the perms again ( you said that it has been checked )
the print statement has to be wrapped as a line to html page,
use "<br>" tags to see the error message in the html page
What is the return code of system function call ?

One more thing, make sure, it had happened several times,
make sure of the absolute path of the filename

My cgi script is working fine. Paths in system calls are correct.

Here are my system calls from a cgi script:

unless (system("/mypath/A.pl") == 0 ) {
print "<br><br>1 system calls failed $?<br>";
}
unless (system("/bin/cat /mypath/TMP.txt > /mypath/fileA.txt"") == 0) {
print "<br><br>2 system calls failed $?<br>";
}
unless (system("/bin/cp -f /mypath/fileA.txt /mypath/fileB.txt") == 0) {
print "<br><br>3 system calls failed $?<br>";
}

Return codes seen from browser:

1 system calls failed 3328


2 system calls failed 65280


3 system calls failed 256

did you check the web server logs yet?

I'm having the same problems, and I don't think I have access to the web server logs.