linux編程筆記_1 簡單的線程使用

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

void *thread_function (void * arg);

char message[]="Hello World";

void *thread_function(void * args){
printf("thread is running . the argument was %s \n",(char *)args);
sleep(3);
strcpy(message,"Bye");
pthread_exit("thank you for the cpu time");
}


int main()
{
    int res;
    pthread_t a_thread;
    void * thread_result;
    res=pthread_create(&a_thread,NULL,thread_function,(void *) message);
    res=pthread_join(a_thread,&thread_result);
    printf("return %s\n",(char*)thread_result);
    printf("Message is %s \n",message);
    return 0;
}

thread1.c:(.text+0x6f): undefined reference to `pthread_create'

thread1.c:(.text+0x85): undefined reference to `pthread_join

當出現上面錯誤時，說明編譯 參數有問題   gcc thread1.c -o thread  -lpthread