tom.c

用五个实例来解释linux下的c编程

/* tom.c v3.0 */

#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>

#define FIFO "message.fifo"

int main()
{
  int fifo;
  char msg[] = "I love you.\n";
  ssize_t s;

  /* Create FIFO. */
  if ((mkfifo(FIFO, 0666)<0) && (errno!=EEXIST))
    perror("mkfifo");

  if (fork()==0) {
    /* Execue Jerry. */
    if(execvp("./jerry", NULL)<0)
      perror("execvp");
  } else {
    /* Open FIFO. */
    fifo = open(FIFO, O_WRONLY);
    if(fifo < 0) {
      perror("open");
    }
    /* Write message. */
    s = write(fifo, &msg, sizeof(msg)-1);
    /* Close file. */
    close(fifo);
  }

  exit(EXIT_SUCCESS);
}