How to Compile and Run CGI Scripts in C Examples in Linux Apache Server

How to Compile and Run CGI Scripts in C Examples in Linux Apache Server :-

first let us create an HTML file(testcgi.html) :

it can be made using keditor, geditor or vi editor

Enter First Number :

Enter Second Number :

use form action http://localhost/cgi-bin/sum.cgi

then we have to make a C Program (sum.c):

#include<stdio.h>

#include<stdlib.h>

int main(void)

{

char *data;

long m,n;

printf("%s%c%c\n","Content-Type:text/html;charset=iso-8859-1",13,10);

printf("\n");

printf("HTML Form values are added...\n");

data = getenv("QUERY_STRING");

if(data == NULL)

printf("Error! Error in passing data from form to script.");

else if(sscanf(data,"m=%ld&n=%ld",&m,&n)!=2)

printf("Error! Invalid data. Data must be numeric.");

else

printf("The Sum of %ld and %ld is %ld.",m,n,m+n);

return 0;

}

To Compile:

in linux login root user and go to command line terminal

root# cc sum.c -o sum.cgi

root# chmod 777 sum.cgi

root# cp sum.cgi /var/www/cgi-bin/

otherwise find cgi-bin directory and put it there.

then put html file some where

root# cp testcgi.html /var/www/html/

next run apache web server:

root# service httpd restart

then open a browser and give an address like

http://localhost/cgi-bin/testcgi.html

Enter two numbers and the result will be displayed in the next page.