hello_arg2.c

来自「Pthread lib库完整说明文档」· C语言 代码 · 共 72 行

/******************************************************************************
* FILE: hello_arg2.c
* DESCRIPTION:
*   A "hello world" Pthreads program which demonstrates another safe way
*   to pass arguments to threads during thread creation.  In this case,
*   a structure is used to pass multiple arguments.
* 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];

struct thread_data
{
   int	thread_id;
   int  sum;
   char *message;
};

struct thread_data thread_data_array[NUM_THREADS];

void *PrintHello(void *threadarg)
{
   int taskid, sum;
   char *hello_msg;
   struct thread_data *my_data;

   sleep(1);
   my_data = (struct thread_data *) threadarg;
   taskid = my_data->thread_id;
   sum = my_data->sum;
   hello_msg = my_data->message;
   printf("Thread %d: %s  Sum=%d\n", taskid, hello_msg, sum);
   pthread_exit(NULL);
}

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

sum=0;
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++) {
  sum = sum + t;
  thread_data_array[t].thread_id = t;
  thread_data_array[t].sum = sum;
  thread_data_array[t].message = messages[t];
  printf("Creating thread %d\n", t);
  rc = pthread_create(&threads[t], NULL, PrintHello, (void *) 
       &thread_data_array[t]);
  if (rc) {
    printf("ERROR; return code from pthread_create() is %d\n", rc);
    exit(-1);
    }
  }
pthread_exit(NULL);
}