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14. Example 1 (ser1.c & cli1.c).
This example shows the minimum of what is required. Future
examples will provide incremental improvements over this one.
The client and the server use the stream-like Unix domain
protocol to communicate. Since Unix domain protocol is not
really a network protocol, the client and the server must run on
the same machine. The server provides a very simple service:
echo the message back to the client.
/*
* cli1.c - test for Unix domain stream socket (client part).
*
This is a very **crude** program.
*/
#include
<sys/types.h>
#include
<sys/socket.h>
#include
<sys/un.h>
#include
<string.h>
#include
<stdio.h>
#include
<string.h>
char serversockname[]="serversocket";
int main()
{
int sd, n;
char buf[256];
struct sockaddr_un server_addr;
char mesg[]="hello from client";
// create client socket
sd = socket(PF_UNIX, SOCK_STREAM, 0);
// construct the server address
server_addr.sun_family = AF_UNIX;
strcpy(server_addr.sun_path, serversockname);
// request connection to serversoc
connect(sd, (struct sockaddr *)&server_addr, sizeof(server_addr));
// send a message to server
write(sd, mesg, strlen(mesg)+1);
// read the result back from server
read(sd, buf, sizeof(buf));
// print out the result
printf("server echoed '%s'\n", buf);
exit(0);
}
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/*
*
ser1.c
test for Unix domain stream socket (server part)
*
This is a very **crude** program.
*/
#include
<string.h>
#include
<sys/types.h>
#include
<sys/socket.h>
#include
<sys/un.h>
#include
<string.h>
#include
<errno.h>
char serversockname[]="serversocket";
main()
{
int sd, nsd, n;
char buf[256];
struct sockaddr_un server_addr;
struct sockaddr_un client_addr;
int
client_addr_len;
// set up listening socket sd
sd = socket(PF_UNIX, SOCK_STREAM, 0);
// construct the server address
server_addr.sun_family = PF_UNIX;
strcpy(server_addr.sun_path, serversockname);
// bind server address to socket sd
bind(sd, (struct sockaddr *)&server_addr, sizeof(server_addr));
// set socket sd to a listening socket
listen(sd, 1);
// accept connection request
client_addr_len = sizeof(client_addr);
nsd = accept(sd, (struct sockaddr *)&client_addr, &client_addr_len);
// data transfer on connected socket ns
n = read(nsd, buf, sizeof(buf));
write(nsd, buf, n);
exit(0);
}
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