例程:
#include "SDL_thread.h"
#include "SDL_mutex.h"
int potty = 0;
int gotta_go;
int thread_func(void *data)
{
SDL_mutex *lock = (SDL_mutex *)data;
int times_went;
times_went = 0;
while ( gotta_go ) {
SDL_mutexP(lock); /* 锁住potty */
++potty;
printf("线程%d 正在使用potty/n", SDL_ThreadID());
if ( potty > 1 ) {
printf("哦,有人在用potty!/n");
}
--potty;
SDL_mutexV(lock);
++times_went;
}
printf("好了/n");
return(times_went);
}
int main(int argc,char *argv[])
{
const int progeny = 5;
SDL_Thread *kids[progeny];
SDL_mutex *lock;
int i, lots;
/* 创建同步锁 */
lock = SDL_CreateMutex();
gotta_go = 1;
for ( i=0; i<progeny; ++i ) {
kids[i] = SDL_CreateThread(thread_func, lock);
}
SDL_Delay(5*1000);
SDL_mutexP(lock);
printf("都完成了吗?/n");
gotta_go = 0;
SDL_mutexV(lock);
for ( i=0; i<progeny; ++i ) {
SDL_WaitThread(kids[i], &lots);
printf("线程 %d 用过potty %d 次了/n", i+1, lots);
}
SDL_DestroyMutex(lock);
returtn 0;
}
|