条件变量和互斥锁

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<unistd.h>
#include<pthread.h>
#include<errno.h>
#include<iostream>
using namespace std;

/*提示出租车到达的条件变量*/
pthread_cond_t taxiCond = PTHREAD_COND_INITIALIZER;
/*同步锁*/
pthread_mutex_t taxiMutex = PTHREAD_MUTEX_INITIALIZER;

int travelerCount = 0;

void *traveler_arrive(void* name) {
    cout << "Travel:" << (char*)name << "need a taxi now!" << endl;
    pthread_mutex_lock(&taxiMutex);
    travelerCount++;
    pthread_cond_wait(&taxiCond,&taxiMutex);
    pthread_mutex_unlock(&taxiMutex);
    cout << "Traveler：" << (char*)name << "now got a taxi!" << endl;
    pthread_exit((void*)0);
}
void *taxi_arrive(void *name) {
    cout << "Taxi:" << (char*)name << "arrives." << endl;
    while (1) {
        pthread_mutex_lock(&taxiMutex);
        if (travelerCount > 0) {
            pthread_cond_signal(&taxiCond);
            pthread_mutex_unlock(&taxiMutex);
            break;
        }
        pthread_mutex_unlock(&taxiMutex);
    }
    pthread_exit((void*)0);
}

int main() {
    pthread_t tids[3];
    int iRet = pthread_create(&tids[0], NULL, taxi_arrive, (void*)(" Jack "));
    if (iRet) {
        printf("pthread_creat error: iRet = %d\n", iRet);
        return iRet;
    }
    printf("Time passing by\n");
    sleep(1);
    iRet = pthread_create(&tids[1], NULL, traveler_arrive, (void*)(" Susan "));
    if (iRet) {
        printf("pthread_creat error: iRet = %d\n", iRet);
        return iRet;
    }
    printf("Time passing by\n");
    iRet = pthread_create(&tids[2], NULL, taxi_arrive, (void*)(" Mike "));
    if (iRet) {
        printf("pthread_creat error: iRet = %d\n", iRet);
        return iRet;
    }
    printf("Time passing by\n");
    sleep(1);
    void *retval;
    for (int i = 0; i < 3; i++) {
        iRet = pthread_join(tids[i], &retval);
        if (iRet) {
            printf("Join error: iRet = %d\n", iRet);
            return iRet;
        }
        printf("retval = %ld\n", (long)retval);
    }
    return 0;
}