Linux下一个简单的线程示例程序

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>

void *thread_function( void *arg );
char message[] = "Hello World!\n";

int main()
{
    int res;
    pthread_t a_thread;
    void *thread_result;

    /* 创建线程 */
    res = pthread_create( &a_thread, NULL, thread_function, ( void* )message );
    if ( res != 0 )
    {
        perror( "Thread creation failed" );
        exit( EXIT_FAILURE );
    }

    printf( "Waiting for thread to finish...\n" );
    /* 等待线程结束 */
    res = pthread_join( a_thread, &thread_result );

    if ( res != 0 )
    {
        perror( "Thread join failed" );
        exit( EXIT_FAILURE );
    }

    printf( "Thread joined, it returned %s\n", ( char* )thread_result );
    printf( "Message is now %s\n", message );
    exit( EXIT_SUCCESS );
}

void *thread_function( void *arg )
{
    printf( "thread_function is running. Argument was %s\n", ( char* )arg );
    sleep( 3 );
    strcpy( message, "Bye!" );
    /* 线程返回值 */
    pthread_exit( (void*)"Thank you for the CPU time" );
}

主要涉及到3个函数：pthread_create, pthread_join, pthread_exit。

int
     pthread_create(pthread_t *thread, const pthread_attr_t *attr,
         void *(*start_routine)(void *), void *arg);

int
     pthread_join(pthread_t thread, void **value_ptr);

void
     pthread_exit(void *value_ptr);