Skip site navigation (1)Skip section navigation (2) 
Date:      Thu, 29 Sep 2005 20:47:09 +0800
From:      "Gary Li-126" <liguoqiang_0121@126.com>
To:        <freebsd-stable@freebsd.org>
Subject:   Problem About how to use shared posix semaphore
Message-ID:  <001701c5c4f3$e82ac020$c700a8c0@lgq>
next in thread | raw e-mail | index | archive | help 

Hi,
    I always get the error message:"Operation not permitted" When I use sem_init set pshared argument equal 1. Compiling as : "gcc -o sem_test sem_test.c -lc_r". My freebsd ver is release 5.4 p6.
    Test code appear below:
      1 #include <sys/types.h>
      2 #include <string.h>
      3 #include <stdio.h>
      4 #include <sys/stat.h>
      5 #include <unistd.h>
      6 #include <fcntl.h>
      7 #include <errno.h>
      8 #include <pthread.h>
      9 #include <semaphore.h>
     10
     11 int main(int argc, char ** argv)
     12 {
     13     sem_t   mutex;
     14     if (-1 == sem_init (&mutex, 1, 1)) {
     15         printf("sem init error:%s\n", strerror(errno));
     16         exit(0);
     17     }
     18     sem_wait (&mutex);
     19     printf("sem wait ok:\n");
     20     sem_post (&mutex);
     21     sem_destroy (&mutex);
     22     return 0;
     23 }

Best regards,
Gary Li

Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?001701c5c4f3$e82ac020$c700a8c0>