UDP ECHO SERVER

PROGRAM:

SERVER SIDE:

#include<stdio.h>

#include<unistd.h>

#include<sys/types.h>

#include<netinet/in.h>

#include<string.h>

#include<sys/socket.h>

#define LOCAL_SERVER_PORT 1500

#define MAX_MSG100

int main(int argc.char *argv[])

{

Int sd,rc,n,clien;

Struct sockaddr_in cliaddr,servaddr;

Char msg[MAX_MSG];

Sd=socket[AF_INET<SOCK_DGRAM,0);

If(sd>0)

{

Printf(“%s cannot open socket\n”,argv[0]);

Exit(0);

}

Servaddr.sin_family=AF_INET;

Servaddr.sin_addr.s_addr=hton1(INADDR_ANY);

Servaddr.sin_port=htons(local_server_port);

Rc=bind(sd,struct sockaddr *)eservaddr,sizeof(servaddr));

If(rc<0)

{

Printf(“%s:cannot bind port number %d \n”);

Argv[0],local_server_port);

Exit(0);

}

if(n<0)

{printf(“%s :cannot receive data\n”);

Continue;

}

Print(“received message is %s”,mag);

}

Return 0;

}

CLIENT SIDE:

#include<stdio.h>

#include<string.h>

#include<sys/types.h>

#include<netinet/in.h>

#include<sys/socket.h>

#define REMOTE_SERVER_PORT 1500

#define MAX_MSG100

Int main(int argc,char *argv[])

{

Int sd,rc,I;

Struct sockaddr_in cliaddr,remote servaddr;

Struct hostenet *h;

If(argc<3)

{

Printf(“usage:%s<server><data1>----<data>\n”.argv[0]);

Exit(1);

}

H=gethostbyname(argv[1]);

If(h-==null)

{

printf(“%s:unknown host’%s’\n”,argv[0],argv[1]);

exit(1);

}

Remote servaddr.sin_family=h->h_addrtype;

Memcpy(cchar*)&remote servaddr.sin_addr.s_addr,h->h_addr_list[0],h->h_length)l

Remote servaddr.sin_port=htons(REMOTE_SERVER_PORT);

Sd=socket(SF_INET,SOCK_DGRAM,0);

If(sd<0)

{

Printf(“%s:cannot open socket \n “,argv[0]);

exit(0);

}

If(rc<0)

{

Printf(“%s:cannot send date%d\n”,argv[0],i-1);

Close(sd);

Exit(1);

]

}

Return 1;

}

OUTPUT:

SERVER SIDE:

"ftpse.c" 60L, 1216C written

[ME04@TELNET ~]$ cc ftpse.c

[ME04@TELNET ~]$ ./a.out

Waiting for the dad from upd

Cannot receive the data

[ME04@TELNET ~]$

CLIENT SIDE:

"ftpcl.c" 51L, 1137C written

[ME04@TELNET ~]$ cc ftpcl.c

[ME04@TELNET ~]$ ./a.out

Cannot open socket

Hai baby!!

Received message hai baby!!