Breaking down the code,
an introduction to Perl.
#!/usr/local/bin/perl
#
&readparse;
print "Content-type: text/html\n\n";
#*****************BEGIN BODY*************
The first line of every CGI in Unix is the path to the program which will
run it. Remember, yours may be different because you substitued the path
to Perl on your machine. The server will follow that path, locate Perl, and then
use the Perl interpreter to execute the program. This is the only line
which begins with a hash mark (#) and has some meaning to the program.
Throughout the remainder of the program, the # symbol is a comment, and
the program will disregard anything which follows it.
The third line is one command, &readparse; .
This calls a
subroutine (like executing a function in JavaScript) located down below the
body, which imports all of the text entered in the HTML form.
The fourth line is required for all CGI programs. It tells the server
that anything we choose to print should be returned as an HTML document.
These lines will never change, so from now on we will only focus on the
contents of the BODY section.
Look at the BODY of
our program