linux 缺少pthread gcc,Linux中对pthread_create的未定义引用

#include

#include

#define NUM_THREADS 5

void *PrintHello(void *threadid)

{

long tid;

tid = (long)threadid;

printf("Hello World! It's me, thread #%ld!\n", tid);

pthread_exit(NULL);

}

int main (int argc, char *argv[])

{

pthread_t threads[NUM_THREADS];

int rc;

long t;

for(t=0; t

printf("In main: creating thread %ld\n", t);

rc = pthread_create(&threads[t], NULL, PrintHello, (void *)t);

if (rc){

printf("ERROR; return code from pthread_create() is %d\n", rc);

exit(-1);

}

}

pthread_exit(NULL);

}但是当我在我的机器上编译它(运行Ubuntu Linux 9.04)时,我收到以下错误:

corey@ubuntu:~/demo$ gcc -o term term.c

term.c: In function ‘main’:

term.c:23: warning: incompatible implicit declaration of built-in function ‘exit’

/tmp/cc8BMzwx.o: In function `main':

term.c:(.text+0x82): undefined reference to `pthread_create'

collect2: ld returned 1 exit status这对我没有任何意义,因为标题包含pthread.h,它应具有pthread_create函数。有什么想法会出错吗?