The form server
The form server is a program, in any language.
It must reside in a directory that has been configured
for access to the Web server when it receives data from a form.
Because forms can be accessed and submitted by anyone
who can view the form page on the Web, form servers represent a potential
security problem for the server system. Thus, access is generally
restricted to programs stored in a directory to which access is strictly
limited. This makes it awkward to test form serving programs if you
do not have access to that directory. To help students on this system,
as simple testing scheme is available.
The program gentest produces a file in the /tmp directory
and returns a message to the browser from which it was invoked.
Use the test program by specifying
action=http://www.csc.villanova.edu/cgi-bin/cgi-bin/gentest.pl
in your form.
When you submit the form, a generic response will appear
on your browser screen and the data sent by your form will appear in the
file
/tmp/testscript
on renoir.villanova.edu
You can copy that file to your own directory and test
your own program file.
For example, if your program is called serve.pl,
and your have copied testscript into the same directory, test your program
by typing
serve.pl<testscript
Once again, note that the form server program can do anything
that any other program can do, given the same permissions. The program
can query and update a database, perform computations or complex logical
operations, read and write files, etc. The only limitation is the
access rights. A program running in the cgi-bin directory generally
runs as user = Nobody with no rights to create files (except in /tmp) and
no rights to access any other files unless they are open to all users.
The server program can be written in any language.
It must be in an executable form, ready to be invoked by the server when
data arrives from a form.
Many form server programs are written in perl.
The perl program that responds to our sample
form is
gen.pl
[
Villanova
Homepage | CSC Homepage
| CSC Faculty