shithub: 9intro

ref: 2b99422480d596ebc26921c87c6bb81a07949f3e
dir: /progs/cecho.c.ms/

.P1
.ps -1
.ti -1i
.B
.BX cecho.c
.ps +1
.CW
.ps -2
.vs .15i
#include <u.h>
#include <libc.h>

void
main(int argc, char* argv[])
{
	int	cfd, lfd, dfd;
	long	nr;
	char	adir[40];
	char	ldir[40];
	char	buf[1024];

	cfd = announce("tcp!*!9988", adir);
	if (cfd < 0)
		sysfatal("announce: %r");
	print("announced tcp!*!9988 in %s\en", adir);
.ps +2
.P2
.P1
.ps -2
.vs .15i
	for(;;){
		lfd = listen(adir, ldir);
		if (lfd < 0)
			sysfatal("listen: %r");
.ps +2
.P2
.P1
.ps -2
.vs .15i
		switch(fork()){
		case -1:
			sysfatal("fork: %r");
		case 0:
			close(cfd);
			dfd = accept(lfd, ldir);
			if (dfd < 0)
				sysfatal("can't accept: %r");
			close(lfd);
			print("accepted call at %s\en", ldir);
			for(;;){
				nr = read(dfd, buf, sizeof buf);
				if (nr <= 0)
					break;
				write(dfd, buf, nr);
			}
			print("terminated call at %s\en", ldir);
			exits(nil);
		default:
			close(lfd);
		}
	}
}
.ps +2
.P2