sock_un_server.c

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stddef.h>
#include <sys/socket.h>
#include <sys/un.h>
#include "error.h"

#define SOCK_PATH "/tmp/hello.socket"
#define BUFFER_SIZE 1024

int main(void)
{
    int sfd, cfd, size;
    struct sockaddr_un s_addr, peer_addr;
    socklen_t peer_addr_size;

    char buf[BUFFER_SIZE];
    int read_size;

    memset(&s_addr,    0, sizeof(s_addr));
    memset(&peer_addr, 0, sizeof(peer_addr));
    unlink(SOCK_PATH);
    
    // create socket
    s_addr.sun_family = AF_UNIX;
    strcpy(s_addr.sun_path, SOCK_PATH);
    if ((sfd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
        err_sys("socket");

    // bind
    size = offsetof(struct sockaddr_un, sun_path) + strlen(s_addr.sun_path);
    if (bind(sfd, (struct sockaddr*)&s_addr, size) < 0)
        err_sys("bind");

    // listen
    if(listen(sfd, SOMAXCONN) < 0)
        err_sys("listen");

    // accept socket
    peer_addr_size = sizeof(peer_addr_size);
    if ((cfd = accept(sfd, (struct sockaddr*)&peer_addr, &peer_addr_size)) < 0 )
        err_sys("accept");

    {
        read_size = read(cfd, buf, BUFFER_SIZE);
        printf("%s\n", buf);
    }
    
    close(cfd);
    close(sfd);
    unlink(SOCK_PATH);

    return EXIT_SUCCESS;
}