#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/select.h>

#define BUFSIZE 4096
#define error(format, ...) { fprintf (stderr, format, __VA_ARGS__); exit (1); }

main(int argc, char **argv){


    /* setup connection */

    if (argc != 2) { 
	error("usage %s <unix socket>\n", argv[0]); 
    }
    int sock_fd = socket(PF_UNIX, SOCK_STREAM,0);
    struct sockaddr_un server;
    if (-1 == sock_fd) { 
	perror("can't open socket"); 
	exit(1); 
    }

    server.sun_family = PF_UNIX;
    strcpy(server.sun_path, argv[1]);
    
    if (-1 == connect(sock_fd, 
		      (const struct sockaddr *) &server, 
		      sizeof(server))){
	perror("can't connect to socket");
	exit(1);
    }


    /* dispatch data */
    while (1){
	int stdin_bytes = -1;
	int sock_bytes = -1;

	fd_set inset;
	unsigned char buffer[BUFSIZE];

	FD_ZERO(&inset);  
	if (stdin_bytes) FD_SET(0, &inset);        // watch stdin
	if (sock_bytes)  FD_SET(sock_fd, &inset);  // watch socket input

	if (-1 == select(sock_fd+1,&inset,0,0,0)){
	    perror("select error");
	    exit(1);
	}

	if (stdin_bytes && FD_ISSET(0, &inset)){
	    stdin_bytes = read(0, &buffer, BUFSIZE);
	    // read stdin
	    if (stdin_bytes < 0) { perror("can't read stdin"); exit(1); }

	    // write to socket
	    write(sock_fd, &buffer, stdin_bytes);
	}

	if (sock_bytes && FD_ISSET(sock_fd, &inset)){
	    sock_bytes = read(sock_fd, &buffer, BUFSIZE);
	    // read stdin
	    if (sock_bytes < 0) { perror("can't read socket"); exit(1); }
	    
	    // write to socket
	    write(1, &buffer, sock_bytes);
	}

	if (!(stdin_bytes || sock_bytes)) exit(0); // return when both EOF
    }
}