Testing a script

This form uses this perl script to interpret the information from the user. The perl script should be placed in a cgi-bin directory. The copy linked to from this page is only so that you can see it or download a copy for your own use.

The script was posted to the net by S.E.Brenner@bioc.cam.ac.uk, and contains its own copyright statement.

Test script using a form to collect information

Test script without a form

If you don't want to use a form, you can use the get method which puts a fixed query in the link that causes the script to be invoked.

Next Steps

If you wish to develop a cgi-script in the Computing Science department at Newcastle, you must first contact webmaster.cs@ncl.ac.uk to ask for the necessary configuration changes. This will normally only be granted if:

You are studying one or more computing science modules ; and
you need this facility for part of your course work (rather than for personal use).

There are a few common errors that you should be careful to avoid:-

If you write some perl which contains a syntax error, and to access this without checking for syntax errors first. On the web, you are simply told that the script ran but returned no data when this happens. Please check that the script compiles by running it outside the web first, even if you cannot provide the correct input data that way. Although there are no guarantees, if a script fails to run, the web server has been configured to return a form offering to show you the last few lines of the error logs, in case this is any help.
Please remember that the perl interpretor is not always in the same directory. On pontop it is in /usr/local/bin, so your perl script needs to start with
#!/usr/local/bin/perl
If writing any sort of compiled program, note that pontop is not running linux. You must compile your program or perl module on pontop itself, or on burnhope.
If writing C++ cgi-bin programs, you MAY need to compile them with a -R flag specifying a directory name to search for shared library at runtime. Try running your program on pontop directly, and if this fails run
ldd your-program-name.
If this shows unresolved libraries, such as libstdc++.a then adding
-R /usr/local/lib
to your compile line should help.
You can't put your scripts or programs in a sub directory of your cgi-bin. With the current set-up in this department, you cannot do this. For example:
http://www.cs.ncl.ac.uk/people/c.r.ritson/cgi-bin/sub/script.cgi?Field1=One
is split into four parts:
1. The first part http://www.cs.ncl.ac.uk/people/c.r.ritson/cgi-bin is used to indicate to the server that a program is to be executed and its output returned. This is set up on a per-user basis.
2. The next single path name componant sub is taken to be the name of the program to be executed.
3. The rest of the path name script.cgi is passed to this script via its PATH_INFO environment variable.
4. Finally, this example contains a parameter, Field1=One&Field2=Two which is also passed in to the script.

webmaster.cs@ncl.ac.uk        7th September 1995 .. 13th October 2000 ...