hello_arg1.c

来自「Pthread lib库完整说明文档」· C语言 代码 · 共 55 行

/******************************************************************************
* FILE: hello_arg1.c
* DESCRIPTION:
*   A "hello world" Pthreads program which demonstrates one safe way
*   to pass arguments to threads during thread creation.
* AUTHOR: Blaise Barney
* LAST REVISED: 04/05/05
******************************************************************************/
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#define NUM_THREADS	8

char *messages[NUM_THREADS];

void *PrintHello(void *threadid)
{
   int *id_ptr, taskid;

   sleep(1);
   id_ptr = (int *) threadid;
   taskid = *id_ptr;
   printf("Thread %d: %s\n", taskid, messages[taskid]);
   pthread_exit(NULL);
}

int main(int argc, char *argv[])
{
pthread_t threads[NUM_THREADS];
int *taskids[NUM_THREADS];
int rc, t;

messages[0] = "English: Hello World!";
messages[1] = "French: Bonjour, le monde!";
messages[2] = "Spanish: Hola al mundo";
messages[3] = "Klingon: Nuq neH!";
messages[4] = "German: Guten Tag, Welt!"; 
messages[5] = "Russian: Zdravstvytye, mir!";
messages[6] = "Japan: Sekai e konnichiwa!";
messages[7] = "Latin: Orbis, te saluto!";

for(t=0;t<NUM_THREADS;t++) {
  taskids[t] = (int *) malloc(sizeof(int));
  *taskids[t] = t;
  printf("Creating thread %d\n", t);
  rc = pthread_create(&threads[t], NULL, PrintHello, (void *) taskids[t]);
  if (rc) {
    printf("ERROR; return code from pthread_create() is %d\n", rc);
    exit(-1);
    }
  }

pthread_exit(NULL);
}