HTTP is a protocol for transmitting and receiving information on the internet. It allows clients to send requests to servers and receive responses. Common HTTP requests are GET and POST. CGI (Common Gateway Interface) is a standard for interfacing external applications with information servers like HTTP servers. It allows programs to be run on a server and to handle requests that are similar to HTML forms. When a CGI program is executed, it has access to environment variables containing information about the request.

1. HTTP və CGI
Adil Əliyev
http://neats.az

2. Məlumat necə ötürülür?

3. Məlumat necə ötürülür?

4. HTTP nə olan şeydir?

5. GET
GET / HTTP/1.1
Connection: Keep­Alive
User­Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.1
(KHTML, like Gecko) Chrome/21.0.1180.89 Safari/537.1
Accept: text/*, image/jpeg, image/png, image/*, */*
Accept­Encoding: x­gzip, gzip, identity
Accept­Charset: Any, utf­8, *
Accept­Language: en, en_US
Host: www.google.com

6. GET
HTTP/1.1 200 OK
Date: Thu, 24 Jan 2002 17:33:52 GMT
Server: Apache/1.3.14
Last­Modified: Mon, 21 Jan 2002 22:08:33 GMT
Etag: “47bc6­25e0­3c4c9161”
Accept­Ranges: bytes
Content­Length: 9696
Connection: close
Content­Type: text/html
­­ blank line­­
­­ HTML entity ­­

7. POST
POST /path/script.cgi HTTP/1.0
From: frog@jmarshall.com
User­Agent: HTTPTool/1.0
Content­Type: application/x­www­form­urlencoded
Content­Length: 32
page=index&id=15

8. CGI nədir?

9. CGI
http://example.com/toplama.cgi?m=4&n=2
...
HTTP_ACCEPT="text/html,application/xhtml+xml,application/xml;q=0
.9,*/*;q=0.8"
HTTP_ACCEPT_CHARSET="ISO­8859­1,utf­8;q=0.7,*;q=0.7"
HTTP_ACCEPT_ENCODING="gzip, deflate"
HTTP_ACCEPT_LANGUAGE="en­us,en;q=0.5"
HTTP_CONNECTION="keep­alive"
HTTP_HOST="example.com"
HTTP_USER_AGENT="Mozilla/5.0 (Windows NT 6.1; WOW64; rv:5.0)
Gecko/20100101 Firefox/5.0"
...
QUERY_STRING="var1=value1&var2=with%20percent%20encoding"
REMOTE_ADDR="127.0.0.1"
REMOTE_PORT="63555"
REQUEST_METHOD="GET"
REQUEST_URI="/toplama.cgi?m=4&n=2"
...

10. CGI
http://example.com/toplama.cgi?m=4&n=2
#include <stdio.h>
#include <stdlib.h>
int main(void)
{
char *data;
long m,n;
printf("%s%c%cn", "Content­Type:text/html;charset=utf­
8",13,10);
printf("<p>Toplama</p>n");
data = getenv("QUERY_STRING");
sscanf(data,"m=%ld&n=%ld",&m,&n);
printf("<p> %ld + %ld = %ld.",m,n,m*n);
return 0;
}

11. CGI və POST
uses dos;
var
a:string;
c:char;
begin
writeln('Content­Type:text/html',#10#13);
a:='';
while not eof(input) do
begin
read(c);
a:= a+c;
end;
writeln('POST: ',a);
end.

12. İstinadlar
● RFC 2616 (http://tools.ietf.org/html/rfc2616)
● RFC 3875 (http://tools.ietf.org/html/rfc3875)

13. Təşəkkür edirəm!