The feasibility of using char * STR for the second parameter of send (;) in unixdomaisocket

The content to be written today is to test whether the second parameter in send (,) can use the char * STR pointer.

Conclusion: Yes!

The server code is as follows:

/* 2012-06-07-the code is modified based on the http://beej.us/guide/bgipc/output/html/multipage/unixsock.html. Download the original code * echos. C -- the echo server for echoc. c; demonstrates UNIX sockets */# include <stdio. h> # include <stdlib. h> # include <errno. h> # include <string. h> # include <sys/types. h> # include <sys/socket. h> # include <sys/UN. h> # define sock_path "/home/Tian/mysocket" int main (void) {int S, S2, T, Len; struct sockaddr_un local, remote; char STR [100]; if (S = socket (af_unix, sock_stream, 0) =-1) {perror ("socket"); exit (1) ;} local. sun_family = af_unix; strcpy (local. sun_path, sock_path); unlink (local. sun_path); Len = strlen (local. sun_path) + sizeof (local. sun_family); If (BIND (S, (struct sockaddr *) & Local, Len) =-1) {perror ("bind"); exit (1 );} if (Listen (S, 5) =-1) {perror ("listen"); exit (1) ;}for (;) {int done, N; printf ("waiting for a connection... \ n "); t = sizeof (remote); If (s2 = accept (S, (struct sockaddr *) & remote, & T) =-1) {perror ("accept"); exit (1);} printf ("connected. \ n "); do {memset (STR, 0, sizeof (STR); n = Recv (S2, STR, 5, 0); If (n <0) {perror ("Recv"); break;} else if (n = 0) {break;} // printf ("echo> % s \ n", STR ); //} while (1); close (S2);} return 0 ;}

Server execution result:

The client code is as follows:

/* 2012-06-07-the code is modified based on the http://beej.us/guide/bgipc/output/html/multipage/unixsock.html. Download the original code ** echoc. C -- the echo client for echos. c; demonstrates UNIX sockets */# include <stdio. h> # include <stdlib. h> # include <errno. h> # include <string. h> # include <sys/types. h> # include <sys/socket. h> # include <sys/UN. h> # define sock_path "/home/Tian/mysocket" int main (void) {int S, T, Len; struct sockaddr_un remote; If (S = socket (af_unix, sock_stream, 0) =-1) {perror ("socket"); exit (1);} printf ("t Rying to connect... \ n "); remote. sun_family = af_unix; strcpy (remote. sun_path, sock_path); Len = strlen (remote. sun_path) + sizeof (remote. sun_family); If (connect (S, (struct sockaddr *) & remote, Len) =-1) {perror ("Connect"); exit (1 );} printf ("connected. \ n "); int num = 5; char * STR = (char *) calloc (5, sizeof (char); While (1) {sprintf (STR, "% d", num); // format num in 10 to STR // printf ("strlen --- % d \ n ", Strlen (STR); // print the STR length // If (send (S, STR, strlen (STR), 0) =-1) {perror ("send"); exit (1);} printf ("Num --- % d \ n", num); // print num to judge while () whether the loop runs num --; If (num = 0) break;} If (STR! = NULL) {STR = NULL; free (STR); // release the memory space occupied by STR} Close (s); Return 0 ;}

Client execution result:

Based on the execution results of the server and client, you can determine that the program runs normally.