This is not Perl-specific, but - as a general troubleshooting tool for headers and other "invisible" interaction stuff, I've always found "netcat" very useful. If I've got a CGI file (e.g., "info.cgi") that's not giving me any output, and it appears to run fine from the command line, I'll fire up my webserver and request that file via "nc": 

[ben@Tyr:~]$ nc localhost 80
GET /info.cgi
<HTML>
<HEAD><TITLE>403 Forbidden</TITLE></HEAD>
<BODY BGCOLOR="#cc9999" TEXT="#000000" LINK="#2020ff" VLINK="#4040cc">
<H2>403 Forbidden</H2>
The requested URL '/info.cgi' resolves to a file which is marked executable but is not a CGI file; retrieving it is forbidden.
<HR>
<ADDRESS><A HREF="http://www.acme.com/software/thttpd/">thttpd/2.23beta1 26may2002</A></ADDRESS>
</BODY>
</HTML>
[ben@Tyr:~]$

The above tells me that my webserver doesn't recognize this file as CGI - so now I know what to troubleshoot. 


-- 
Human history becomes more and more a race between education and catastrophe. -- HG Wells

In reply to Re: Malformed headers from LibXSLT by oko1
in thread Malformed headers from LibXSLT by Anonymous Monk

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