git.ozlabs.org Git - ccan/blob - ccan/fdpass/_info

   1 #include "config.h"
   2 #include <stdio.h>
   3 #include <string.h>
   4
   5 /**
   6  * fdpass - routines to pass a file descriptor over a socket.
   7  *
   8  * This code handles all the hairy details of fd passing.
   9  *
  10  * License: CC0 (Public domain)
  11  * Maintainer: Rusty Russell <rusty@rustcorp.com.au>
  12  *
  13  * Example:
  14  *      // Outputs hello!
  15  *      #include <ccan/fdpass/fdpass.h>
  16  *      #include <sys/socket.h>
  17  *      #include <sys/un.h>
  18  *      #include <stdio.h>
  19  *      #include <stdlib.h>
  20  *      #include <unistd.h>
  21  *
  22  *      static void child(int sockfd)
  23  *      {
  24  *              char buffer[6];
  25  *              int newfd = fdpass_recv(sockfd);
  26  *              read(newfd, buffer, sizeof(buffer));
  27  *              printf("%.*s\n", (int)sizeof(buffer), buffer);
  28  *              exit(0);
  29  *      }
  30  *
  31  *      static void parent(int sockfd)
  32  *      {
  33  *              int pfds[2];
  34  *
  35  *              pipe(pfds);
  36  *              fdpass_send(sockfd, pfds[0]);
  37  *              close(pfds[0]);
  38  *              write(pfds[1], "hello!", 6);
  39  *              exit(0);
  40  *      }
  41  *
  42  *      int main(void)
  43  *      {
  44  *              int sv[2];
  45  *
  46  *              socketpair(AF_UNIX, SOCK_STREAM, 0, sv);
  47  *              if (fork() == 0)
  48  *                      child(sv[0]);
  49  *              else
  50  *                      parent(sv[1]);
  51  *      }
  52  */
  53 int main(int argc, char *argv[])
  54 {
  55         /* Expect exactly one argument */
  56         if (argc != 2)
  57                 return 1;
  58
  59         if (strcmp(argv[1], "depends") == 0)
  60                 return 0;
  61
  62         return 1;
  63 }
  64
  65