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下面举例 :创建52个线程
一个教授,一个助教,50个学生
#include <unistd.h> /* Symbolic Constants */ #include <sys/types.h> /* Primitive System Data Types */ #include <errno.h> /* Errors */ #include <stdio.h> /* Input/Output */ #include <stdlib.h> /* General Utilities */ #include <pthread.h> /* POSIX Threads */ #include <string.h> /* String handling */ #include <time.h> /* prototype for thread routine */ void print_message_function ( void *ptr ); /* struct to hold data to be passed to a thread this shows how multiple data items can be passed to a thread */ typedef struct str_thdata { int thread_no; char message[100]; }thdata; int main() { pthread_t thread[52]; /* thread variables */ thdata data[52]; /* structs to be passed to threads */ /* initialize data to pass to thread 1 */ data[0].thread_no = 1; strcpy(data[0].message, "TY doctor!"); /* initialize data to pass to thread 2 */ data[1].thread_no = 2; strcpy(data[1].message, "yang teaching assistant!"); /* initialize data to pass to thread 3-52 */ for(int i=2;i<52;i++){ data[i].thread_no = i+1; strcpy(data[i].message,"student"); } srand((int)time(NULL)); /* create threads 1 and 2 */ pthread_create (&thread[0], NULL, (void *) &print_message_function, (void *) &data[0]); usleep(1); pthread_create (&thread[1], NULL, (void *) &print_message_function, (void *) &data[1]); usleep(1); for(int i=2;i<52;i++){ pthread_create (&thread[i], NULL, (void *) &print_message_function, (void *) &data[i]); int m=rand()%200; usleep(m); } /* Main block now waits for all threads to terminate, before it exits If main block exits, both threads exit, even if the threads have not finished their work */ for(int j=0;j<52;j++) pthread_join(thread[j], NULL); /* exit */ exit(0); } /* main() */ /** * print_message_function is used as the start routine for the threads used * it accepts a void pointer **/ void print_message_function ( void *ptr ) { thdata *data; data = (thdata *) ptr; /* type cast to a pointer to thdata */ /* do the work */ if(data->thread_no>2){ printf("Thread %2d says %s %2d\n", data->thread_no, data->message,(data->thread_no-2)); } else{ printf("Thread %2d says %s \n", data->thread_no, data->message); } pthread_exit(0); /* exit */ } /* print_message_function ( void *ptr ) */
输出样例
$ gcc -o main main.c -lpthread $ ./main Thread 1 says doctor! Thread 2 says teaching assistant! Thread 3 says student 1 Thread 4 says student 2 Thread 5 says student 3 ...... Thread 51 says student 49 Thread 52 says student 50