man/journal-stream-fd.c

   1 /* SPDX-License-Identifier: MIT-0 */
   2
   3 #include <errno.h>
   4 #include <syslog.h>
   5 #include <stdio.h>
   6 #include <unistd.h>
   7 #include <systemd/sd-journal.h>
   8 #include <systemd/sd-daemon.h>
   9
  10 int main(int argc, char *argv[]) {
  11   int fd;
  12   FILE *log;
  13   fd = sd_journal_stream_fd("test", LOG_INFO, 1);
  14   if (fd < 0) {
  15     errno = -fd;
  16     fprintf(stderr, "Failed to create stream fd: %m\n");
  17     return 1;
  18   }
  19   log = fdopen(fd, "w");
  20   if (!log) {
  21     fprintf(stderr, "Failed to create file object: %m\n");
  22     close(fd);
  23     return 1;
  24   }
  25   fprintf(log, "Hello World!\n");
  26   fprintf(log, SD_WARNING "This is a warning!\n");
  27   fclose(log);
  28   return 0;
  29 }