pthread线程特定数据

• 举个栗子

  • #include <stdio.h>
    #include <stdlib.h>
    #include <unistd.h>
    #include <sys/types.h>
    #include <pthread.h>
    #include <errno.h>
    #include <string.h>
    
    #define ERR_EXIT(m)
        do
        {
            perror(m);
            exit(EXIT_FAILURE);
        }while(0)
    
    typedef struct tsd
    {
        pthread_t tid;
        char* str;
    }tsd_t;
    
    pthread_key_t key_tsd;
    
    void destroy_routine(void* value)
    {
        free(value);
        printf("destroy...
    ");
    }
    
    void* thread_routinne(void* arg)
    {
        tsd_t* value = (tsd_t*)malloc(sizeof(tsd_t));
        value->tid = pthread_self();
        value->str = (char*)arg;
    
        pthread_setspecific(key_tsd,value);
        
        printf("%s setspecific %p
    ",(char*)arg,value);
    
        value = pthread_getspecific(key_tsd);
        printf("tid=0x%x str=%s
    ",value->tid,value->str);
        sleep(2);
    
        value = pthread_getspecific(key_tsd);
        printf("tid=0x%x str=%s
    ",value->tid,value->str);
        return NULL;
    }
    
    int main(void)
    {
        pthread_key_create(&key_tsd,destroy_routine);
        
        pthread_t tid1;
        pthread_t tid2;
        pthread_create(&tid1, NULL, thread_routinne, "thread1");
        pthread_create(&tid2, NULL, thread_routinne, "thread1");
    
        pthread_join(tid1,NULL);
        pthread_join(tid2,NULL);
    
        pthread_key_delete(key_tsd);
    
    
        return 0;
    }

  • 分析

    • 线程特定数据对每个线程都有一个独立的数据