Premature end of script headers - What, I have no idea! - perl

I try to execute a simple perl script on my server and I get an internal 500 server and when I check the error logs it shows:
Premature end of script headers: test.pl
Here is the perl script:
#!/usr/bin/perl -w
print "Content-type: text/plain\n\n";
print "testing...\n";
My cgi-bin folder has permissions of 0755. The script itself is also 0755. The script is owned by apache and its in the group apache. The script works fine via the command line.
What is the problem and how can I fix this?!
Thanks all for any help!
Update
Interesting find in suExec:
2010-09-14 17:38:28]: uid: (10001/som) gid: (2522/2522) cmd: test.pl
[2010-09-14 17:38:28]: target uid/gid (10001/2522 or 2521) mismatch with directory (48/0) or program (48/0)
But my cgi-folder is the same as the test.pl script - is it referring to another directory?

Plenty of good advice: How can I troubleshoot my Perl CGI script.
Update having seen your suexec error message: Looks like your server needs the CGI program to be owned by the same user as the directory. Try changing the ownership of the file.

There are a lot of good troubleshooting suggestions for Perl scripts giving that error message on PerlMonks: start here. I don't see any specific errors in your script, and it looks like you've covered the file permissions, so I'd start with the Apache configuration suggestions.

Use CGI module e.g.
use CGI qw/:standard/;
$q = CGI->new;
print $q->header('text/html');
print "testing...\n";

Related

LAMPP - CGI-Script not working

Hello
I have got a LAMPP Webserver. I tried to open a CGI Script called "Hello.cgi".
It contains:
#!/usr/bin/perl
print "Hello World.\n";
The path is: /opt/lampp/htdocs/dashboard/cgi-bin/hello.cgi
When I open: "127.0.0.1/dashboard/cgi-bin/hello.cgi", I get following:
Server error!
The server encountered an internal error and was unable to complete your request.
Error message:
End of script output before headers: hello.cgi
If you think this is a server error, please contact the webmaster.
The CGI Script is written in Perl.
If you need more informations about my problem, say it, please.
~~runasas
Firstly, you should never write a Perl program without including the lines use strict; and use warnings;.
Secondly, if you have problems with a CGI program, you should check the web server error log for more details of the problem.
Thirdly, the output from a CGI program needs to include a content type header. So you'll want to add the following:
print "Content-Type: text/plain\015\012\015\012";
This becomes easier if you use the CGI module:
use CGI;
print header('text/plain');
But really, in 2016, you shouldn't be writing CGI programs - there are plenty of good alternatives available.

Why isn't this perl cgi script redirecting?

I have a perl cgi script that is exactly the following:
#!/usr/bin/perl -w
use CGI;
$query = new CGI;
print $query->redirect("http://www.yahoo.com");
At the command line things look OK:
$perl test.pl
Status: 302 Moved
Location: http://www.yahoo.com
When I load it in the browser, http://localhost/cgi-bin/test.pl, the request gets aborted, and depending on the browser I get various messages:
Connection reset by server.
No data received.
The only research I could find on this issue, stated that a common problem is printing some data or header before the redirect call, but I am clearly not doing that here.
I'm hosting it from a QNX box with the default slinger server.
The code works fine on my machine, check the following
Check the error logs, eg: tail /var/log/http/error_log
Do the chmod/chown permissions match other working CGi scripts, compare using ls -l
Does printing the standard hello world work? Change your print statement to
print $query->header(), 'Hello World';
Add the following for better errors
use warnings;
use diagnostics;
use CGI::Carp 'fatalsToBrowser';
at the command line use slinger will return some basic use options. For logging you need both syslogd and -d enabled in slinger. Ie
slinger -d &
Then look to /var/log/syslog for errors

Can't get perl scripts to work (500 internal server error) on a tuxlite LAMP stack (Debian 6 Squeeze)

Does anyone who has experience with Tuxlite know how to get Perl scripts working? I've tried many, many things from tutorials on the web about getting Perl scripts to work with Apache without success. I keep getting a 500 internal server error. I'm allowing .cgi and .pl scripts in .htaccess.
My script is a hello world script
#!/usr/bin/perl print "Content-Type: text/html\n\n"; print "Hello World.";
I assume that this is not a apache/web problem.
Try your script on the shell and check the output.
(I assume that it does not run in the shell.)
May be your perl is not set up or a module is missing.
If that works, please add your script to your question.

Internal Server Error when the perl code run

I am getting the internal server error when run the perl script.I put the file into the cgi-bin folder and set the permission 755. please let me know the How can I resolve this?
There are two files in cgi-bin folder.One is perldigger.cgi. It is working fine its url is http://mts.marketsignalsoftware.com/cgi-bin/perldigger.cgi and the 2nd is test.cgi. It is giving the internal error. I wrote the simple code into it and url is http://mts.marketsignalsoftware.com/cgi-bin/test.cgi.
#!/usr/bin/perl -w
# Program to do the obvious
print 'Hello world.';
# Print a message
Thanks
Check your error logs and you will see a message about missing headers, maybe something like Premature end of script headers ....
The first output of a CGI script should always be a content type header.
Try
#!/usr/bin/perl -w
print "Content-type: text/plain\n\n";
print 'Hello world.';
Obligatory trouble shooting link for the next problem you have:
How can I troubleshoot my Perl CGI script?

Why doesn't my Perl CGI script work?

I really do not get how to run a Perl file. I have uploaded my .pl to the cgi-bin then chmod to 755. Then when i go to run the file i just get a 500 internal server error.
**/cgi-bin/helloworld.pl**
#!/usr/bin/perl
print 'hello world';
Any ideas as to what I am doing wrong?
Read the official Perl CGI FAQ.
That'll answer this, and many other questions you may have.
For example: "My CGI script runs from the command line but not the browser. (500 Server Error)"
Hope this helps!
You probably need something like
print "Content-type: text/html\n\n";
before your print statement. Take a look at http://httpd.apache.org/docs/2.0/howto/cgi.html#troubleshoot
It would help to know what server you are using, and the exact error message that's showing up in the server's logs. I'd guess that, if you are using Apache, you'll see something like "Premature end of script headers".
Look into using CGI::Carp to output fatal errors to the browser. use CGI::Carp qw(fatalsToBrowser);
Also, please definitely do use the CGI module to output any needed information such as headers/html/whatever. Printing it all is the wrong way to do it.
EDIT: You will also definitely be able to check an error log of some sort.
Perhaps you need my Troubleshooting Perl CGI scripts
First, find out the path to perl on that system and make sure the shebang line is correct. Giving more information about the system and the web server would also help others diagnose.
Then, try:
#!/path/to/perl/binary
use strict;
use warnings;
$| = 1;
use CGI qw( :default );
print header('text/plain'), "Hello World\n";
Make sure that you can run the script from a shell prompt, without invoking it through Perl. In other words, you should be able to go to your cgi-bin directory and type:
./helloworld.pl
and get output. If that doesn't work, fix that. In looking at the output, the first line must be:
Content-Type: text/html
(Or text/plain or some other valid MIME type.)
If that's not the case, fix that.
Then you must have an empty line before the body of your page is printed. If there's no empty line, your script won't work as a CGI script. So your total output should look like this:
Content-Type: text/html
hello world
If you can run your script and that's the output, then there's something weird going on. If Apache is not logging the error to an error_log file somewhere, then maybe there's some problem with it.
Did you enable Apache to server .pl files as CGI scripts? Check your Apache config file, or (quick but not guaranteed test) try changing the file extension to .cgi. Also, make sure your shebang line (#!) is at the very top. Finally, check the line endings are Unix if your server is Linux. And yes, test it from the command-line, and use strict; for better feedback on potential errors.