pthread创建线程及遇到问题解决

出现的错误：invalid conversion from `void*' to `void*(*)(void*)

原来是定义的void reader_function();

pthread_create(&reader,NULL,(void*)&reader_function,NULL);

这样的代码用gcc编译不出问题，用gcc编译有问题。为了两者都没有问题，所以就改为了 void * reader_function();

这样改过之后，又出现了新的问题：invalid conversion from `void*(*)()' to `void*(*)(void*)'

这时又需要改变reader_function函数，给这个函数加上参数变为：void * reader_function(void*);

执行makefile时出现下面错误

undefined reference to `pthread_create'

要增加 -lpthread

gcc pthreadTest.cpp -o pthreadTest -lpthread

#include <stdio.h>#include <stdlib.h>#include <pthread.h>#include <unistd.h>void* reader_function(void*args);void writer_function();pthread_mutex_t mutex;int main(void) {    puts("Hello World!!!");    pthread_t reader;    pthread_mutex_init(&mutex,NULL);    pthread_create(&reader,NULL,reader_function,NULL);//    sleep(1);    writer_function();    return EXIT_SUCCESS;}void writer_function(){    sleep(1);    int i=0;    while(1){        printf("this is writer :%d\n",i);        i++;    }}void* reader_function(void * agrs){    sleep(1);    int i=0;    while(1){        printf("this is reader reader reader :%d\n",i);        i++;    }    int *a = 0;    return a;}

使用互斥锁pthread_mutex_t，实现同一进程中，某些资源的同步。

#include <stdio.h>#include <stdlib.h>#include <pthread.h>#include <unistd.h>void* reader_function(void*args);void writer_function();pthread_mutex_t mutex;int tickets = 1000;int main(void) {    puts("Hello World!!!");    pthread_t reader;    pthread_mutex_init(&mutex,NULL);    pthread_create(&reader,NULL,reader_function,NULL);//    sleep(1);    writer_function();    return EXIT_SUCCESS;}void writer_function(){    while(1){        pthread_mutex_lock(&mutex);        if(tickets>0){            printf("this is writer :%d\n",tickets--);        }else{            break;        }        pthread_mutex_unlock(&mutex);    }}void* reader_function(void * agrs){    while(1){        pthread_mutex_lock(&mutex);        if(tickets>0){            printf("this is reader to sell tickets :%d\n",tickets--);        }else{            break;        }        pthread_mutex_unlock(&mutex);    }    int *a = 0;    return a;}