Development of CGI programs based on Apache server

The Apache server was successfully built in the previous section, which describes the development of CGI programs that can be run on Apache servers using the C language

After installing Apache server, there are some files for developing Apache server under C:\Program files\apache software foundation\apache2.2.

File Description:

Bin:apache Server Software Location

Cgi-bi: Save program written in C language

Conf: saving information for server settings

Error: Handling of Web site sending errors

Htdcocs: Saving HTML programs

Icons: Save icons for developing Apache programs

Include: Save some header files used by the development Web application

Lib: Some of the libraries that are used to develop Web applications are saved

Logs: Log

Manual:apache settings for the server language

Modlules: Save some dynamic link libraries

Program Example 1: develop a CGI version of the Hello World program

Development tools: VS2012 Apache Server

Development steps:

First compile the following code using VS2012

#include <stdio.h>void main () {    //Set HTML language    printf ("content-type:text/html\n\n");    Print Hello World, I come from    a line break in CGI//html for <br>    printf ("Hello World, I'm from CGI!<br>");}

After the compilation succeeds in the Debug folder in the project directory there will be an EXE format executable file, I compiled the program generated by the CGI programming. exe

Copy the exe file to the C:\Program files\apache software Foundation\apache2.2\cgi-bin directory, and modify the format of the file to change the CGI programming. EXE to HELLO.CGI

Finally, enter http://localhost/cgi-bin/hello.cgi in IE browser

Program Example 2: traverse all environment variables in Apache server

First compile the following code using VS2012

#include <stdio.h> #include <stdlib.h>void main () {    //Set HTML language    printf ("content-type:text/html\n \ n ");    printf ("eviroments:<br>");    Used to save environment variables    extern char** environ;    Traverse all environment variables in the CGI for    (int i=0;; i++)    {        if (NULL = = Environ[i])        {break            ;        }        Print all environment variables in CGI        printf ("%s<br>", Environ[i]);}    }

Copy the exe file to the C:\Program files\apache software Foundation\apache2.2\cgi-bin directory, and modify the format of the file to change the CGI programming. EXE to EVIROMENTS.CGI

Finally, enter in IE browser: http://localhost/cgi-bin/eviroments.cgi

Program Example 3: use environment variables to get the type of server

#include <stdio.h> #include <stdlib.h>void main () {    //Set HTML language    printf ("content-type:text/html\ N\n ");    printf ("%s", getenv ("Server_software"));}

Execution Result:

Program Example 4: use environment variables to output web information

#include <stdio.h> #include <stdlib.h>void main () {    //Set HTML language    printf ("content-type:text/html\n \ n ");    The name, version,   and other platform-based additional information for the browser that submitted the form.    printf ("%s<br><br>", getenv ("Http_user_agent"));    CGI Script runtime host name and IP address    printf ("%s<br><br>", getenv ("SERVER_NAME"));    The type of your server such as:    printf ("%s<br><br>", getenv ("Server_software"));    Point to the path to this CGI script,    printf ("%s<br><br>", getenv ("Script_name"));    Host name of the submission script, this value cannot be set.    printf ("%s<br><br>", getenv ("Remote_host"));         The host IP address of the submission script.    printf ("%s<br><br>", getenv ("REMOTE_ADDR"));          Run the CGI version of    printf ("%s<br><br>", getenv ("Gateway_interface"));           The TCP port that the server is running on.    printf ("%s<br><br>", getenv ("Server_port"));    The HTTP protocol that the server is running.    printf ("%s<br><br>", getenv ("Server_protocol"));}

Execution Result:

Program Example 5: add hyperlinks to Web pages

#include <stdio.h> #include <stdlib.h>void main () {    //Set HTML language    printf ("content-type:text/html\n \ n ");    printf ("<a href= ' http://www.baidu.com ' >www.baidu.com</a>");}

Execution Result:

Program Example 6: use environment variables to implement parameter 1 pass

#include <stdio.h> #include <stdlib.h>void main () {    //Set HTML language    printf ("content-type:text/html\n \ n ");    Char name[256];    Use environment variables to get passed parameters    char* queryString = getenv ("query_string");    Parse a string into another string    //To print%s in the obtained string to the CNAME    sscanf (queryString, "name=%s", name);        Prints the passed parameters of    printf ("Hello%s<br>", Name);}

Compile the above code using VS2012, after the successful compilation, there will be an EXE file in the Debug folder in the project directory, the EXE file will be modified to name.cgi, and copied to C:\Program Files\apache software In Foundation\apache2.2\cgi-bin

Finally, enter Http://localhost/cgi-bin/name.cgi?name=Tom in the browser

Execution results

Program Example 7: pass multiple parameters using environment variables

#include <stdio.h> #include <stdlib.h>void main () {    //Set HTML language    printf ("content-type:text/html\n \ n ");    int i1,i2;//defines 2 variables for receiving passed arguments    //using environment variables to get passed parameters    char* queryString = getenv ("query_string");    Parse a string into another string    //To print%s in the obtained string to the CNAME    sscanf (queryString, "i1=%d&i2=%d", &i1, &i2);    printf ("%d+%d=%d", I1, I2, i1+i2);}

Compile the above code using VS2012, after the successful compilation, there will be an EXE file in the Debug folder in the project directory, the EXE file will be modified to sum.cgi, and copied to C:\Program Files\apache software Foundation In \apache2.2\cgi-bin

Finally, enter http://localhost/cgi-bin/sum.cgi?i1=12&i2=13 in the browser

Execution results

Program Example 8: using HTML in CGI

Enter the following HTML language in Notepad and save it in HTML format

Place the saved HTML file in the C:\Program files\apache software Foundation\apache2.2\htdocs directory.
Enter http://localhost/sum.html in the browser
Execution Result:


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Development of CGI programs based on Apache server