Socket Programming Introduction Source Code

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http://www.linuxsocket.org/

soooo many people have asked or had problems with BASIC Socket Programming, might as well post a template source code right?

Code:

#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/socket.h>
#include <resolv.h>
#define PORT_HTTP	81
#define PORT_TIME	13
#define PORT_FTP	21
#define SERVER_ADDR	"127.0.0.1"
#define MAXBUF		1024

int main(int argc, char* argv[])
{	int acc;
	int sockfd;
	struct sockaddr_in dest;
	char buffer[MAXBUF];
	
	/* Open socket for streaming */
	if( (sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0)
	{
		perror("Socket");
		exit(errno);
	}
	/* Init Server Address/port struct */
	bzero(&dest,sizeof(dest));
	dest.sin_family = AF_INET;
	if(argv[1] == NULL)
		dest.sin_port = htons(PORT_FTP);
	else
	{
		scanf("%d",&acc);
		dest.sin_port = htons(acc);
	}
	if ( inet_aton(SERVER_ADDR, &dest.sin_addr.s_addr) == 0)
	{
		perror(SERVER_ADDR);
		exit(errno);
	}
	if( connect(sockfd, (struct sockaddr*)&dest,sizeof(dest)) != 0)
	{
		perror("Connect ");
		exit(errno);
	}
	
	bzero(buffer,MAXBUF);
	recv(sockfd,buffer,sizeof(buffer),0);
	printf("%s",buffer);

	close(sockfd);
	return 0;
}

Slightly modified because I am working on a scanner but here is some code that opens up FTP and stuff...
When I finish the scanner, I will post that too.

Er, just some thoughts:

Code:

#define PORT_HTTP	81    /* Port 80 is the reserved HTTP port */

bzero(&dest,sizeof(dest));  /* bzero() has been deprecated.  Use memset(). */ 

Also, what is this?

Code:

bzero(buffer,MAXBUF);
recv(sockfd,buffer,sizeof(buffer),0);
printf("%s",buffer);

Your first use of buffer is to zero it out. Save yourself the function call and initialize 'buffer' with:

Code:

char buffer[MAXBUF] = { 0 };

Since you know the size of the buffer (MAXBUF), why call sizeof()? Also, how will the user know if recv() fails?

[EDIT]
Here is a socket tutorial written a while back that goes into more detail.
[/EDIT]

This isn't my source code
it is Linux SOcket's
Mine is:
http://cyber.homeunix.net:81/c/scan.c

I am still new to Network Programming but I am a SEMI_PRO at Kernel Modules...

Still need to find more time to read all the information out there, thanks, when I rewrote my client.c (Linux Socket's name for that program) I noticed that too, well some things