TCP Time Server Program

TCP Time Server Program

Purpose - Server to send time to the client(TCP)

Program Status: Tested, Program Difficulty: Very Easy

Program written by G.Vivek Venkatesh

Screen-shot of output:


Program

server.c 

#include "stdio.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "string.h"
#include "sys/socket.h"
#include "stdlib.h"
#include "unistd.h"
#include "time.h"
main()
{
int sd,i,len,bi,nsd,port;
char content[30],buff[30],last_received[30];
struct sockaddr_in ser,cli;
if((sd=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))==-1)
{
printf("\n Socket problem");
return 0;
}
printf("\n Socket created\n");
bzero((char*)&cli,sizeof(ser));
printf("ENTER PORT NO:\n");
scanf("%d",&port);
printf("\n Port Address is %d\n:",port);
ser.sin_family=AF_INET;
ser.sin_port=htons(port);
ser.sin_addr.s_addr=htonl(INADDR_ANY);

bi=bind(sd,(struct sockaddr *)&ser,sizeof(ser));
if(bi==-1)
{
printf("\n bind error, port busy, plz change port in client and server");
return 0;
}
i=sizeof(cli);
listen(sd,5);
nsd = accept(sd,((struct sockaddr *)&cli),&i);

if(nsd==-1)
{
printf("\ncheck the description parameter\n");
return 0;
}
printf("\nConnection accepted");

time_t ticks;
ticks=time(NULL);
snprintf(buff,sizeof(buff),"%24s\r\n",ctime(&ticks));

send(nsd,buff,30,0);
printf("\n Bye..");
send(nsd,"EOF",4,0);
close(sd);
close(nsd);
return 0;
}


client.c
#include "stdio.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "string.h"
#include "sys/socket.h"
#include "stdlib.h"
#include "unistd.h"
int main()
{
int sd,con,port,i;
char content[30];
struct sockaddr_in cli;
if((sd=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))==-1)
{
printf("\n Socket problem");
return 0;
}
bzero((char*)&cli,sizeof(cli));
cli.sin_family = AF_INET;
printf("ENTER PORT NO");
scanf("%d",&port);
cli.sin_port=htons(port);
cli.sin_addr.s_addr=htonl(INADDR_ANY);
con=connect(sd,(struct sockaddr*)&cli,sizeof(cli));
if(con==-1)
{
printf("\n connection error");
return 0;
}
i=recv(sd,content,30,0);
printf("Received from server %s\n",content);
close(sd);
return 0;
}
Download Source code

tserver.c

tclient.c

Packet Capturing using Raw Socket Program

Packet Capturing using Raw Socket Program

Question

Program using Raw Sockets(like Packet Capturing)

Note

You must have root privilege in order to run this program.

Download Source Code(preferred than viewing it Live on blog)

click here.........program

click here.........output

Program

(rawudp.c)

#include "unistd.h"
#include "stdio.h"
#include "sys/socket.h"
#include "netinet/ip.h"
#include "netinet/udp.h"

#define PCKT_LEN 8192

// The IP header's structure
struct ipheader {
unsigned char iph_ihl:5, iph_ver:4;
unsigned char iph_tos;
unsigned short int iph_len;
unsigned short int iph_ident;
unsigned char iph_flag;
unsigned short int iph_offset;
unsigned char iph_ttl;
unsigned char iph_protocol;
unsigned short int iph_chksum;
unsigned int iph_sourceip;
unsigned int iph_destip;
};

// UDP header's structure
struct udpheader {
unsigned short int udph_srcport;
unsigned short int udph_destport;
unsigned short int udph_len;
unsigned short int udph_chksum;
};

// Function for checksum calculation.
unsigned short csum(unsigned short *buf, int nwords)
{ //
unsigned long sum;
for(sum=0; nwords>0; nwords--)
sum += *buf++;
sum = (sum >> 16) + (sum &0xffff);
sum += (sum >> 16);
return (unsigned short)(~sum);
}

int main(int argc, char *argv[])
{
int sd;
char buffer[PCKT_LEN];
// Our own headers' structures
struct ipheader *ip = (struct ipheader *) buffer;
struct udpheader *udp = (struct udpheader *) (buffer + sizeof(struct ipheader));
// Source and destination addresses: IP and port
struct sockaddr_in sin, din;
int one = 1;
const int *val = &one;

memset(buffer, 0, PCKT_LEN);

// Create a raw socket with UDP protocol
sd = socket(PF_INET, SOCK_RAW, IPPROTO_UDP);
if(sd < sin_family =" AF_INET;" sin_family =" AF_INET;" sin_port =" htons(atoi(argv[2]));" sin_port =" htons(atoi(argv[4]));" s_addr =" inet_addr(argv[1]);" s_addr =" inet_addr(argv[3]);">iph_ihl = 5;
ip->iph_ver = 4;
ip->iph_tos = 16;
ip->iph_len = sizeof(struct ipheader) + sizeof(struct udpheader);
ip->iph_ident = htons(54321);
ip->iph_ttl = 64; // hops
ip->iph_protocol = 17; // UDP
ip->iph_sourceip = inet_addr(argv[1]);//Source IP address
ip->iph_destip = inet_addr(argv[3]);// destination IP address

// Fabricate the UDP header.
udp->udph_srcport = htons(atoi(argv[2]));//source port
udp->udph_destport = htons(atoi(argv[4]));//destination port
udp->udph_len = htons(sizeof(struct udpheader));
// Calculate the checksum
ip->iph_chksum = csum((unsigned short *)buffer, sizeof(struct ipheader) + sizeof(struct udpheader));

if(setsockopt(sd, IPPROTO_IP, IP_HDRINCL, val, sizeof(one)) < count =" 1;">iph_len, 0, (struct sockaddr *)&sin, sizeof(sin)) < 0)
{
perror("sendto() error");
exit(-1);
}
else
{
printf("Count #%u - sendto() is OK.\n", count);
sleep(2);
}
}
close(sd);
return 0;
}

Remote Procedure Call Program in C

Remote Procedure Call Program in C

Question

To implement Remote Procedure Call, and perform addition and subtraction of two numbers.

(Explanation will be given soon).

Program

simp.x

#define VERSION_NUMBER 1

%#define foo 127

struct operands {

int x;

int y;

};

program SIMP_PROG {

version SIMP_VERSION {

int ADD(operands) = 1;

int SUB(operands) = 2;

} = VERSION_NUMBER;

} = 555555555;

simpclient.c

/* RPC client for simple addition example */

#include "stdio.h"

#include "simp.h" /* Created for us by rpcgen - has everything we need ! */

/* Wrapper function takes care of calling the RPC procedure */

int add( CLIENT *clnt, int x, int y) {

operands ops;

int *result;

/* Gather everything into a single data structure to send to the server */

ops.x = x;

ops.y = y;

/* Call the client stub created by rpcgen */

result = add_1(&ops,clnt);

if (result==NULL) {

fprintf(stderr,"Trouble calling remote procedure\n");

exit(0);

}

return(*result);

}

/* Wrapper function takes care of calling the RPC procedure */

int sub( CLIENT *clnt, int x, int y) {

operands ops;

int *result;

/* Gather everything into a single data structure to send to the server */

ops.x = x;

ops.y = y;

/* Call the client stub created by rpcgen */

result = sub_1(&ops,clnt);

if (result==NULL) {

fprintf(stderr,"Trouble calling remote procedure\n");

exit(0);

}

return(*result);

}

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

CLIENT *clnt;

int x,y;

if (argc!=4) {

fprintf(stderr,"Usage: %s hostname num1 num\n",argv[0]);

exit(0);

}

/* Create a CLIENT data structure that reference the RPC

procedure SIMP_PROG, version SIMP_VERSION running on the

host specified by the 1st command line arg. */

clnt = clnt_create(argv[1], SIMP_PROG, SIMP_VERSION, "udp");

/* Make sure the create worked */

if (clnt == (CLIENT *) NULL) {

clnt_pcreateerror(argv[1]);

exit(1);

}

/* get the 2 numbers that should be added */

x = atoi(argv[2]);

y = atoi(argv[3]);

printf("%d + %d = %d\n",x,y, add(clnt,x,y));

printf("%d - %d = %d\n",x,y, sub(clnt,x,y));

return(0);

}

simpservice.c

/* Definition of the remote add and subtract procedure used by

simple RPC example

rpcgen will create a template for you that contains much of the code

needed in this file is you give it the "-Ss" command line arg.

*/

#include "simp.h"

/* Here is the actual remote procedure */

/* The return value of this procedure must be a pointer to int! */

/* we declare the variable result as static so we can return a

pointer to it */

int *

add_1_svc(operands *argp, struct svc_req *rqstp)

{

static int result;

printf("Got request: adding %d, %d\n", argp->x, argp->y);

result = argp->x + argp->y;

return (&result);

}

int *

sub_1_svc(operands *argp, struct svc_req *rqstp)

{

static int result;

printf("Got request: subtracting %d, %d\n", argp->x, argp->y);

result = argp->x - argp->y;

return (&result);

}

Compilation and Output

Server

vivek@ubuntu~$ rpcgen -C -a simp.x

vivek@ubuntu~$ cc -o server simpservice.c simp_svc.c simp_xdr.c

vivek@ubuntu~$ ./server

Got request: adding 4, 5

Got request: subtracting 4, 5

Client

vivek@ubuntu~$ cc -o client simpclient.c simp_clnt.c simp_xdr.c

vivek@ubuntu~$ ./client linux 4 5

4 + 5 = 9

4 - 5 = -1

Download Source Code 

One Bit Sliding Window Protocol

One Bit Sliding Window Protocol

Question - To write a C program to Implement One Bit Sliding Window Protocol.

Screenshot of Output


Program

sender.c (server)

#include "stdio.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "string.h"
#include "sys/socket.h"
#include "stdlib.h"
#include "unistd.h"
main()
{
int sd,i,r,bi,nsd,port,frame,prev_frame=0,count=0;;
char ack[5],buff[30];
struct sockaddr_in ser,cli;
if((sd=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))==-1)
{
printf("\n Socket problem");
return 0;
}
printf("\n Socket created\n");
bzero((char*)&cli,sizeof(ser));
printf("ENTER PORT NO:\n");
scanf("%d",&port);
printf("\n Port Address is %d\n:",port);
ser.sin_family=AF_INET;
ser.sin_port=htons(port);
ser.sin_addr.s_addr=htonl(INADDR_ANY);

bi=bind(sd,(struct sockaddr *)&ser,sizeof(ser));
if(bi==-1)
{
printf("\n bind error, port busy, plz change port in client and server");
return 0;
}
i=sizeof(cli);
listen(sd,5);
nsd = accept(sd,((struct sockaddr *)&cli),&i);
if(nsd==-1)
{
printf("\ncheck the description parameter\n");
return 0;
}
printf("\nConnection accepted.");
while(count<5) 
{
ph: 
printf("\nSending FRAME %d to the Receiver...\n",prev_frame);snprintf(buff,sizeof(buff),"%d",prev_frame); 
send(nsd,buff,30,0);
r = recv(nsd,ack,5,0); 
if(strcmp(ack,"ack")==0 || strcmp(ack,"ACK")==0)
{ count++;
if(prev_frame==0) prev_frame=1;
else prev_frame = 0; 
} else if(strcmp(ack,"nak")==0 || strcmp(ack,"NAK")==0)
{ printf("\n NAK: So again sending the Previous frame...\n"); goto ph;
} }
printf("\n Bye..");
send(nsd,"EOF",4,0);
close(sd);
close(nsd);
return 0;
}


receiver.c (client)

#include "stdio.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "string.h"
#include "sys/socket.h"
#include "stdlib.h"
#include "unistd.h"
int main()
{
int sd,con,port,i;
char content[30],ack[3];
struct sockaddr_in cli;
if((sd=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))==-1)
{
printf("\n Socket problem");
return 0;
}
bzero((char*)&cli,sizeof(cli));
cli.sin_family = AF_INET;
printf("ENTER PORT NO");
scanf("%d",&port);
cli.sin_port=htons(port);
cli.sin_addr.s_addr=htonl(INADDR_ANY);
con=connect(sd,(struct sockaddr*)&cli,sizeof(cli));
if(con==-1)
{
printf("\n connection error");
return 0;
}
i=recv(sd,content,30,0);
while(strcmp(content,"EOF") != 0)
{ printf("Received from Sender: Frame %s \n",content); 
ph:
printf("\n Acknowledgement(ACK/NAK) : ");
scanf("%s",ack); if(!(strcmp(ack,"ack")==0 || strcmp(ack,"nak")==0 || strcmp(ack,"ACK")==0 || strcmp(ack,"NAK")==0))
{ printf("\n Not a valid Acknowledgement..use ACK or NAK..\n "); 
goto ph; 
} send(sd,ack,5,0); i=recv(sd,content,30,0);
}
printf("\n\n Bye...");
close(sd);
return 0;
}

Download Source Codes

sender.c

receiver.c

DNS Server Client Program

DNS Server Client Program

(Screenshot of output)

dnsserver.c

#include "stdio.h"
#include "string.h"
#include "stdlib.h"
#include "unistd.h"
#include "errno.h"
#include "sys/socket.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "arpa/inet.h"
#define MAXBUFFLEN 500
int main(int argc,char *argv[])
{
int sockfd,port,bi;
char buff[MAXBUFFLEN-1];
struct sockaddr_in servaddr,cliaddr;
int addr_len,numbytes;
sockfd=socket(AF_INET,SOCK_DGRAM,0);
if(sockfd==-1)
{
perror("Socket()");
return 0;
}
printf("\n Enter the port no:");
scanf("%d",&port);
printf("\n The Port no is:%d",port);
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(port);
servaddr.sin_addr.s_addr = INADDR_ANY;
memset(servaddr.sin_zero,'\0',8);
bi=bind(sockfd,(struct sockaddr*)&servaddr,sizeof(struct sockaddr));
if(bi==-1)
{
perror("bind");
return 0;
}
addr_len = sizeof(struct sockaddr*);
numbytes = recvfrom(sockfd,buff,MAXBUFFLEN-1,0,(struct sockaddr*)&cliaddr,&addr_len);
printf("\n Server Got-Packet from %s",inet_ntoa(cliaddr.sin_addr));
printf("\n Server packet is %d bytes long.",numbytes);
buff[numbytes]='\0';
printf("\n The Server packet contains %s",buff);
close(sockfd);
return 0;
}

dnsclient.c

#include "stdio.h"
#include "string.h"
#include "stdlib.h"
#include "unistd.h"
#include "errno.h"
#include "sys/socket.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "arpa/inet.h"
#include "netdb.h"
int main(int argc,char *argv[])
{
int sockfd,port;
struct sockaddr_in servaddr;
struct hostent *he;
int addr_len,numbytes;
if(argc!=3)
{
fprintf(stderr,"Client Usage : %s \n",argv[0]);
exit(1);
}
if((he=gethostbyname(argv[1]))==NULL)
{
perror("gethostbyname error");
exit(1);
}
sockfd=socket(AF_INET,SOCK_DGRAM,0);
if(sockfd==-1)
{
perror("Socket.");
return 0;
}
printf("\n Enter the port no:");
scanf("%d",&port);
printf("\n The port no is : %d",port);
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(port);
servaddr.sin_addr = *((struct in_addr*)he->h_addr);
memset(&(servaddr.sin_zero),'\0',8);
numbytes = sendto(sockfd,argv[2],sizeof(argv[2]),0,(struct sockaddr*)&servaddr,sizeof(struct sockaddr));
printf("\n Sent %d bytes to %s",numbytes,inet_ntoa(servaddr.sin_addr));
close(sockfd);
return 0;
}

Download Source Code

dnsserver.c

dnsclient.c

UDP Time Server Program

UDP Time Server Program

tserver.c

#include "stdio.h"
#include "string.h"
#include "stdlib.h"
#include "sys/socket.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "time.h>
int main()
{
int sfd,r,bi,port;
char buff[1024];
struct sockaddr_in servaddr,cliaddr;
socklen_t clilen;
sfd=socket(AF_INET,SOCK_DGRAM,0);
if(sfd==-1)
{
perror("Socket");
return 0;
}
memset(servaddr.sin_zero,'\0',sizeof(servaddr.sin_zero));
printf("\n Enter the port no:");
scanf("%d",&port);
printf("\n The port no is:%d",port);
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(port);
servaddr.sin_addr.s_addr = INADDR_ANY;
bi=bind(sfd,(struct sockaddr*)&servaddr,sizeof(servaddr));
if(bi==-1)
{
perror("Bind()");
return 0;
}
clilen = sizeof(cliaddr);
r=recvfrom(sfd,buff,sizeof(buff),0,(struct sockaddr*)&cliaddr,&clilen);
buff[r]=0;
time_t ticks;
ticks = time(NULL);
snprintf(buff,sizeof(buff),"%24s\r\n",ctime(&ticks));
sendto(sfd,buff,sizeof(buff),0,(struct sockaddr*)&cliaddr,sizeof(cliaddr));
exit(0);
return 0;
}

tclient.c

#include "stdio.h"
#include "string.h"
#include "stdlib.h"
#include "sys/socket.h"
#include "sys/types.h"
#include "netinet/in.h"
int main()
{
int listenfd,port,r;
char buff[1024];
struct sockaddr_in servaddr,cliaddr;
socklen_t servlen;
listenfd = socket(AF_INET,SOCK_DGRAM,0);
if(listenfd==-1)
{
perror("Socket");
return 0;
}
memset(servaddr.sin_zero,'\0',sizeof(servaddr.sin_zero));
printf("\n Enter the port no:");
scanf("%d",&port);
printf("\n The port no is:%d",port);
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(port);
servaddr.sin_addr.s_addr = INADDR_ANY;
sendto(listenfd,buff,sizeof(buff),0,(struct sockaddr*)&servaddr,sizeof(servaddr));
r=recvfrom(listenfd,buff,sizeof(buff),0,(struct sockaddr*)&servaddr,&servlen);
buff[r]=0;
printf("\n The time received from the server:%s",buff);
exit(0);
return 0;
}

Download Source Code

tserver.c

tclient.c

UDP Echo Server Client Program

UDP Echo Server Client Program

UDP - User Datagram Protocol

(To know more Click the below link)
http://en.wikipedia.org/wiki/User_Datagram_Protocol

TCP Vs UDP

TCP - Reliable, Ordered, Heavyweight, Streaming.

UDP - Unreliable, Not Ordered, Lightweight, Datagrams.
Screenshot of the Output



Program

Server.c

#include "stdio.h"
#include "sys/types.h"
#include "sys/socket.h"
#include "netinet/in.h"
#include "string.h"
#include "stdlib.h"
int main()
{
int len,sfd,connfd,i=0,r,b,l,port;
char buff[1024],str[1024],c;
struct sockaddr_in servaddr,cliaddr;
socklen_t clilen;
sfd=socket(AF_INET,SOCK_DGRAM,0);
if(sfd==-1)
{
perror("Socket");
exit(-1);
}
memset(servaddr.sin_zero,'\0',sizeof(servaddr.sin_zero));
printf("\n Enter the port no:");
scanf("%d",&port);
printf("\n Port No is %d",port);
servaddr.sin_family=AF_INET;
servaddr.sin_addr.s_addr=INADDR_ANY;
servaddr.sin_port=htons(port);
b=bind(sfd,(struct sockaddr*)&servaddr, sizeof(servaddr));
if(b==-1)
{
perror("bind");
exit(-1);
}
clilen=sizeof(cliaddr);
r=recvfrom(sfd,buff,sizeof(buff),0,(struct sockaddr*)&cliaddr, &clilen);
buff[r]=0;
printf("\n Client:%s",buff);
printf("\n Server:%s",buff);
sendto(sfd,buff,sizeof(buff),0,(struct sockaddr*)&cliaddr,sizeof(cliaddr));
exit(0);
return 0;
}


Client.c

#include "stdio.h"
#include "sys/types.h"
#include "sys/socket.h"
#include "netinet/in.h"
#include "string.h"
#include "stdlib.h"
int main()
{
int len,listenfd,connfd,i=0,r,co,port;
char buff[1024],c;
struct sockaddr_in servaddr,cliaddr;
socklen_t servlen;
listenfd=socket(AF_INET,SOCK_DGRAM,0);
if(listenfd==-1)
{
perror("socket");
exit(-1);
}
memset(servaddr.sin_zero,'\0',sizeof(servaddr.sin_zero));
printf("\n Enter the port no:");
scanf("%d",&port);
printf("\n Port No is : %d",port);
servaddr.sin_family=AF_INET;
servaddr.sin_addr.s_addr=INADDR_ANY;
servaddr.sin_port=htons(port);
printf("\n Client:");
scanf("%s",buff);
sendto(listenfd,buff,sizeof(buff),0,(struct sockaddr*)&servaddr,sizeof(servaddr));
r=recvfrom(listenfd,buff,sizeof(buff),0,(struct sockaddr*)&servaddr, &servlen);
buff[r]=0;
printf("\n Server:%s\n",buff);
exit(0);
return 0;
}


Download The Source Code

UDP_Server.c

UDP_Client.c

TCP Echo Server Program.

TCP Echo Sever program

Purpose - Server must receive messages from client and echo it back to client...

Program Status: Tested, Difficulty level: Easy

Program written by Vivek Venkatesh G

Screen-shot of output:



Program
server.c

#include "stdio.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "string.h"
#include "sys/socket.h"
#include "stdlib.h"
#include "unistd.h"
main()
{
int sd,i,len,bi,nsd,port;
char content[30],buff[30],last_received[30];
struct sockaddr_in ser,cli;
if((sd=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))==-1)
{
printf("\n Socket problem");
return 0;
}
printf("\n Socket created\n");
bzero((char*)&cli,sizeof(ser));
printf("ENTER PORT NO:\n");
scanf("%d",&port);
printf("\n Port Address is %d\n:",port);
ser.sin_family=AF_INET;
ser.sin_port=htons(port);
ser.sin_addr.s_addr=htonl(INADDR_ANY);

bi=bind(sd,(struct sockaddr *)&ser,sizeof(ser));
if(bi==-1)
{
printf("\n bind error, port busy, plz change port in client and server");
return 0;
}
i=sizeof(cli);
listen(sd,5);
nsd = accept(sd,((struct sockaddr *)&cli),&i);
if(nsd==-1)
{
printf("\ncheck the description parameter\n");
return 0;
}
printf("\nConnection accepted");
i = recv(nsd,content,30,0);
send(nsd,content,30,0);
while(strcmp(content,"exit")!=0)
{
printf("\nReceived from client and echoeing it....");
i=recv(nsd,content,30,0);
send(nsd,content,30,0);
}
printf("\n Bye");
send(nsd,"EOF",4,0);
close(sd);
close(nsd);
return 0;
}


client.c

#include "stdio.h"
#include "sys/types.h"
#include "netinet/in.h"
#include "string.h"
#include "sys/socket.h"
#include "stdlib.h"
#include "unistd.h"
int main()
{
int sd,con,port,i;
char content[30];
struct sockaddr_in cli;
if((sd=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP))==-1)
{
printf("\n Socket problem");
return 0;
}
bzero((char*)&cli,sizeof(cli));
cli.sin_family = AF_INET;
printf("ENTER PORT NO");
scanf("%d",&port);
cli.sin_port=htons(port);
cli.sin_addr.s_addr=htonl(INADDR_ANY);
con=connect(sd,(struct sockaddr*)&cli,sizeof(cli));
if(con==-1)
{
printf("\n connection error");
return 0;
}
if(fork())
{
printf("\nEnter the data to be send:");
scanf("%s",content);
while(strcmp(content,"exit")!=0)
{
send(sd,content,30,0);
scanf("%s",content);
}
send(sd,"exit",5,0);
}
else
{
i=recv(sd,content,30,0);
while(strcmp(content,"exit")!=0)
{
printf("Data Echoed from Server: %s\n",content);
i=recv(sd,content,30,0);
}
send(sd,"exit",5,0);
}
close(sd);
return 0;
}


Download Source Code

eserver.c
eclient.c