steveh@hammer.UUCP (05/21/86)
# The rest of this file is a shell script which will extract:
# Makefile README client.c give.c server.c spair.c take.c
echo x - README
cat >README <<'!Funky!Stuff!'
These are demonstrations of Unix domain sockets.
They assume a bug fixed 4.2 (or 4.3) system.
0) To build the examples type:
make
1) client/server example.
# start server
server /tmp/echo &
# run client
client /tmp/echo
hello world...
^D
2) give/take example.
take /tmp/catch &
give /etc/motd /tmp/catch
!Funky!Stuff!
echo x - Makefile
cat >Makefile <<'!Funky!Stuff!'
CFLAGS = -O
DEMOS = client server give take spair
all: ${DEMOS}
clean:; rm -f *.o ${DEMOS}
!Funky!Stuff!
echo x - client.c
cat >client.c <<'!Funky!Stuff!'
/*
* Connect to a unix domain server.
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#define STDIN 0
#define STDOUT 1
main(argc,argv)
char **argv;
{
int s;
struct sockaddr_un sun;
if(argc != 2) {
fprintf(stderr, "Usage: client filename\n");
exit(1);
}
if( (s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
perror("socket");
exit(1);
}
sun.sun_family = AF_UNIX;
strcpy(sun.sun_path, argv[1]);
if( connect(s, (struct sockaddr *) &sun, sizeof(sun)) < 0) {
perror("connect");
exit(1);
}
/* echo loop */
for(;;) {
int mask;
mask = (1<<STDIN) | (1<<s);
if(select(s+1, &mask, (int *) 0, (int *) 0, 0) < 0) {
perror("select");
exit(1);
}
if(mask & (1<<s))
if(copy(s, STDOUT) == 0)
break; /* end of file */
if(mask & (1<<STDIN))
if(copy(STDIN, s) == 0)
break;
}
}
copy(from, to)
{
char buf[BUFSIZ];
register int cc;
cc = read(from, buf, sizeof buf);
if(cc == 0)
return 0;
if(cc < 0) {
perror("read");
exit(1);
}
if(write(to, buf, cc) < 0) {
perror("write");
exit(1);
}
return cc;
}
!Funky!Stuff!
echo x - give.c
cat >give.c <<'!Funky!Stuff!'
/*
* Pass a file to a process
*
* Usage: give file socket
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/uio.h>
struct sockaddr_un sun = { AF_UNIX };
main(argc, argv)
char **argv;
{
int f, s;
struct msghdr msg;
struct iovec iov;
if(argc != 3) {
fprintf(stderr, "Usage: give file socket\n");
exit(1);
}
if(strcmp(argv[1], "-") == 0)
f = 0;
else if( (f = open(argv[1],0)) < 0) {
perror(*argv);
exit(1);
}
if( (s = socket(AF_UNIX, SOCK_DGRAM, 0)) < 0) {
perror("socket");
exit(1);
}
strcpy(sun.sun_path, argv[2]);
msg.msg_name = (caddr_t) &sun;
msg.msg_namelen = sizeof sun;
iov.iov_base = argv[1];
iov.iov_len = strlen(argv[1]);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_accrights = (caddr_t) &f;
msg.msg_accrightslen = sizeof(f);
fprintf(stderr, "give s=%d f=%d\n", f, s);
if(sendmsg(s, &msg, 0) < 0) {
perror("sendmsg");
exit(1);
}
}
!Funky!Stuff!
echo x - server.c
cat >server.c <<'!Funky!Stuff!'
/*
* Unix domain echo server.
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#define STDIN 0
#define STDOUT 1
main(argc,argv)
char **argv;
{
register int cc, s, ns;
char buf[BUFSIZ];
int fromlen;
struct sockaddr_un sun;
struct sockaddr from;
if(argc != 2) {
fprintf(stderr, "Usage: echoserver filename\n");
exit(1);
}
if( (s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
perror("socket");
exit(1);
}
sun.sun_family = AF_UNIX;
strcpy(sun.sun_path, argv[1]);
if( bind(s, (struct sockaddr *) &sun, sizeof(sun)) < 0) {
perror("bind");
exit(1);
}
listen(s, 1);
fromlen = sizeof from;
ns = accept(s, &from, &fromlen);
if(ns < 0)
perror("accept");
else
while( (cc = read(ns, buf, sizeof buf)) > 0)
if(write(ns, buf, cc) < 0) {
perror("server write");
break;
}
if(cc < 0)
perror("server read");
close(ns);
close(s);
unlink(sun.sun_path); /* cleanup */
}
!Funky!Stuff!
echo x - spair.c
cat >spair.c <<'!Funky!Stuff!'
/*
* demonstrate socketsv
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
main(argc, argv)
char **argv;
{
register int child;
int sv[2];
if( socketpair(AF_UNIX, SOCK_STREAM, 0, sv) < 0) {
perror("socketpair");
exit(1);
}
if(write(sv[0], "tick 00", 8) < 0 ||
write(sv[1], "tock 00", 8) < 0) {
perror("write");
exit(1);
}
child = fork();
if(child < 0)
perror("fork");
else if(child == 0) {
flip(sv[0], sv[1]);
} else {
flip(sv[1], sv[0]);
wait((int *) 0);
}
}
flip(from, to)
{
register int i;
register int pid = getpid();
char ibuf[32], obuf[32];;
for(i = 0; i < 10; ++i) {
if(read(from, ibuf, sizeof ibuf) < 0) {
perror("read");
return;
}
printf("%d: %s\n", pid, ibuf);
sprintf(obuf, "%-4.4s %02d", ibuf, i);
if(write(to, obuf, sizeof obuf) < 0) {
perror("write");
return;
}
}
close(from);
close(to);
}
!Funky!Stuff!
echo x - take.c
cat >take.c <<'!Funky!Stuff!'
/*
* Receive a file on a socket
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/uio.h>
struct sockaddr_un sun = { AF_UNIX };
main(argc, argv)
char **argv;
{
register int n;
int s, f;
struct sockaddr from;
struct msghdr msg;
struct iovec iov;
char buf[8*1024];
if(argc != 2) {
fprintf(stderr, "Usage: take socket\n");
exit(1);
}
if( (s = socket(AF_UNIX, SOCK_DGRAM, 0)) < 0) {
perror("socket");
exit(1);
}
strcpy(sun.sun_path, argv[1]);
if( bind(s, &sun, sizeof sun) < 0) {
perror("bind");
exit(1);
}
msg.msg_name = (caddr_t) &from;
msg.msg_namelen = sizeof from;
iov.iov_base = buf;
iov.iov_len = sizeof buf;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_accrights = (caddr_t) &f;
msg.msg_accrightslen = sizeof(f);
fprintf(stderr, "take s=%d\n",s);
n = recvmsg(s, &msg, 0);
if(n < 0) {
perror("recvmsg");
unlink(sun.sun_path);
exit(1);
}
fprintf(stderr, "take got f=%d\n", f);
close(s);
unlink(sun.sun_path);
buf[n] = '\0';
fprintf(stderr, ">%s<\n", buf);
while( (n = read(f, buf, sizeof buf)) > 0)
write(1, buf, n);
if(n < 0)
perror("read");
}
!Funky!Stuff!
--
Stephen Hemminger {ihnp4,decvax,ucbvax}!tektronix!hammer!steveh
Tektronix GWD Networking (503)685-2103