Sockets cause system crash - (nf)

[pedz at smu.UUCP]

#N:smu:18600013:000:4504
smu!pedz    Jun 11 21:22:00 1984

#bug food

We have 4.2 bsd on a Vax 11/780 and I have a problem with sockets.
The two program below are to be used as the client and server of 
a socket.  The server program simply opens the socket and waits
for a client.  When a client comes the server reads from the socket
and echoes what is read to the screen.  The client simply opens the
socket, sends out a messages and closes it.  The code in comments was
to reverse the link and send data from the server back to the client
which is what I want to do eventually.  The getline routine is common
between both programs.  I have tried to copy the lpd and startdeamon
code from the lpr as closely as I thought I needed to.

My problem is not that the two programs do not work (although I can
not find anything which is wrong with them.  The bigger problem is
that when the server is started and then the client is started (from
another terminal) the program does not work.  Typing ^C causes the
client to terminate, then the server is killed.  The first time this
process is done all is fine.  However on the second time, the machine
"crashes".  The crash is put into quotes because it actually does not
crash with a dump and all of that good stuff, but is instead left in a
unuseable state.  Interrupts from the keyboard get serviced but very
slowly (like 10 to 15 seconds to echo a character) and all normal
processing seems to stop.  Eventually the machine is stopped and
rebooted from the console.  (The console is also dead as far as normal
i/o is concerned.  Of course ^P still works which is used to halt the
machine.)

Has this problem been seen before and has it a fix or a work around?
Second, can you spot any obvious error in the program?  (A second
note, all of this is done from a non-privileged state.)  Also, the
IPC primer has an inaccuracy in it when it says that a socket may be
bound to a path simply by putting the pathname and its length as the
second and third arguments to bind.

Thank you for you help,
Perry
convex!smu!pedz

------------------------------------------------------------------
/*
	This is a test program for the server action of a socket
	pair.  It will setup and open a socket, then accept request
	on the socket.  When a request is received, the info will
	be copied from the socket to the screen.  Then a message
	of "SEX IS FUN FOR ALL" will be sent back to the client,
	the socket closed and another request accepted.

*/

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#define SOCKETNAME "/tmp/pedzsocket"

struct	sockaddr_un	socket1, socket2;

main()
{
	int		file1, file2;
	int		len1, len2;
	char	buf[512];
	int		i;

	printf("server1\n");
	unlink(SOCKETNAME);
	file1 = socket(AF_UNIX, SOCK_STREAM, 0);

	socket1.sun_family = AF_UNIX;
	strcpy(socket1.sun_path, SOCKETNAME);
	len1 = strlen(socket1.sun_path) + 2;
	if (bind(file1, &socket1, len1) < 0) {
		perror("server1");
		exit(1);
	}

	printf("server2\n");
	listen(file1, 2);

	printf("server3\n");
	for (;;) {
		len2 = sizeof(socket2.sun_path);
		if (file2 = accept(file1, &socket2, &len2) < 0) {
			perror("server2");
			exit(1);
		}

		printf("server4\n");
		getline(file2, buf);
		printf(buf);

/*		printf("server5\n");
		send(file2, "SEX IS FUN FOR ALL\n", 19, 0);		*/

		close(file2);
		printf("server6\n");
	}
}
---------------------------------------------------------------------
/*
	This is a test program for the client action of a socket
	pair. It will open a socket, bind it to the server, send a message
	and then receive a message.
*/

#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#define SOCKETNAME "/tmp/pedzsocket"

struct	sockaddr_un	socket1, socket2;

main()
{
	int		file1, file2;
	int		len1, len2;
	char	buf[512];
	int		i;

	printf("client1\n");
	file1 = socket(AF_UNIX, SOCK_STREAM, 0);
	if (file1 < 0) {
		perror("client");
		exit(1);
	}

	printf("client2\n");
	socket1.sun_family = AF_UNIX;
	strcpy(socket1.sun_path, SOCKETNAME);
	len1 = strlen(socket1.sun_path) + 2;
	if (connect(file1, &socket1, len1) < 0) {
		perror("client");
		exit(1);
	}

	printf("client3\n");
	send(file1, "LIFE IS BUT A DREAM\n", 20, 0);

/*	printf("client4\n");
	getline(file1, buf);
	printf(buf);		*/

	printf("client5\n");
	close(file1);
}

-----------------------------------------------------------------
getline(i, buf)
int		i;
char	*buf;
{
	char	*temp;
	int		j;

	printf("start getline\n");
	temp = buf;
	do
		j = read(i, temp, 1);
	while (*temp++ != '\n');
	*temp = '\0';
	printf("end getline\n");
}