int nbytes=read（pipefd[0]，&received_事件，sizeof（event_t*）； printf（“读取%d字节\n”，n字节）； 如果（n字节>0） printf（“事件id:%d\n”，已收到\u事件->id）； //释放

int nbytes=read（pipefd[0]，&received_事件，sizeof（event_t*）； printf（“读取%d字节\n”，n字节）； 如果（n字节>0） printf（“事件id:%d\n”，已收到\u事件->id）； //释放结构 免费（已收到活动）； } } 我的等待（1）；//睡眠线程 } 返回0； } //从http://somethingswhichidintknow.blogspot.com/ //2009/09/sleep-in-pthread.html pthread\u mutex\u t fakeMutex=pthread\u mutex\u初始值设定项； pthread_cond_t fakeCond=pthread_cond_初始值设定项； void mywait（int-timeinse） { 结构timespec timeToWait； 现在构造timeval； int-rt； gettimeofday（&now，NULL）； timeToWait.tv_sec=now.tv_sec+timeunsec； timeToWait.tv\u nsec=now.tv\u usec*1000； pthread_mutex_lock（&fakeMutex）； rt=pthread_cond_timedwait（&fakeCond，&fakeMutex，&timeToWait）； pthread_mutex_unlock（&fakeMutex）； }

---

+1仅用于“自然不正常工作”：

$ ...
Writing event 1 to pipe
Received event on pipe
Writing event 2 to pipe
Received event on pipe

$ ...
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event on pipe
Received event o^C

gcc -o test test.c

/* Simple example with two threads and a pipe. One thread writes structs to a 
   pipe every few seconds; the other reads the structs, prints out their info
   and then frees the structs
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <pthread.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/select.h>

void mywait(int timeInSec);

// The events
typedef struct event {
    int id;
    int data;
} event_t;

int id = 0;
int pipefd[2];

void* pump(void *arg) { // Generates events

    for (;;)
    {
        mywait(1); // sleep thread

        printf("writing event #%i to pipe\n", id);

        // generate event
        event_t *event;
        event = malloc(sizeof(*event));
        memset(event, 0, sizeof(*event));
        event->id = id++;

        // write event to pipe
        write(pipefd[1], &event, sizeof(event));

        // NOTE: Free event in other thread
    }
}

int main (int argc, char **argv)
{
    printf("Starting pipe_test.c\n");

    // 1. Create a pipe
    pipe(pipefd);

    // 2. Create thread to pump events into pipe
    pthread_t tid;
    if (pthread_create( &tid, NULL, pump, NULL) != 0) {
        perror("pthread_create:pump");
        exit(-1);
    }

    // 3. Set up selector in main thread to read events off pipe
    int z;
    fd_set readfds; //readable file descriptor
    int selectmax;
    selectmax = pipefd[0] + 1;
    for (;;)
    {
        // Initialize selector
        FD_ZERO( &readfds );
        FD_SET( pipefd[0], &readfds );
        z = select( selectmax, &readfds, NULL, NULL, NULL );

        if( z < 0 ) {
            printf( "select() failed\n");
            // close( pipefd ); //???
            return 1;
        } else {
            if( FD_ISSET( pipefd[0], &readfds ) ) {
                printf("Received event on pipe\n"); // I get a shitton of these

                // Get the pointer to the event struct from the pipe
                // TODO: GOOD WAY TO DO THIS?

                // Free the struct
                // TODO
            }
        }
    }

    return 0;
}

// From http://somethingswhichidintknow.blogspot.com/2009/09/sleep-in-pthread.html
pthread_mutex_t fakeMutex = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t fakeCond = PTHREAD_COND_INITIALIZER;

void mywait(int timeInSec)
{
    struct timespec timeToWait;
    struct timeval now;
    int rt;
    gettimeofday(&now,NULL);

    timeToWait.tv_sec = now.tv_sec + timeInSec;
    timeToWait.tv_nsec = now.tv_usec*1000;

    pthread_mutex_lock(&fakeMutex);
    rt = pthread_cond_timedwait(&fakeCond, &fakeMutex, &timeToWait);
    pthread_mutex_unlock(&fakeMutex);
}

/* Simple example with two threads and a pipe. One thread writes structs to a 
   pipe every few seconds; the other reads the structs, prints out their info
   and then frees the structs
 */

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <pthread.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/select.h>

void mywait(int timeInSec);

// The events
typedef struct event {
    int id;
    int data;
} event_t;

int id = 0;
int pipefd[2];

void* pump(void *arg) { // Generates events

    for (;;)
    {
        printf("writing event #%i to pipe\n", id);

        // generate event
        event_t *event;
        event = malloc(sizeof(event_t));
        memset(event, 0, sizeof(event_t));
        event->id = id++;

        // write event to pipe
        int nbytes = write(pipefd[1], &event, sizeof(event_t*));
        //printf("written %d bytes.\n", nbytes);

        // NOTE: Free event in other thread
        mywait(1); // sleep thread
    }
}

int main (int argc, char **argv)
{
    printf("Starting pipe_test.c\n");

    // 1. Create a pipe
    pipe(pipefd);

    // 2. Create thread to pump events into pipe
    pthread_t tid;
    if (pthread_create( &tid, NULL, pump, NULL) != 0) {
        perror("pthread_create:pump");
        exit(-1);
    }

    // 3. Set up selector in main thread to read events off pipe
    int z;
    fd_set readfds; //readable file descriptor
    int selectmax;
    selectmax = pipefd[0] + 1;
    for (;;)
    {
        // Initialize selector
        FD_ZERO( &readfds );
        FD_SET( pipefd[0], &readfds );
        z = select( selectmax, &readfds, NULL, NULL, NULL );

        if( z < 0 ) {
            printf( "select() failed\n");
            // close( pipefd ); //???
            return 1;
        } else {
            if( FD_ISSET( pipefd[0], &readfds ) ) {
                printf("Received event on pipe\n"); // I get a shitton of these

                // Get the pointer to the event struct from the pipe
                event_t* received_event = NULL;
                int nbytes = read(pipefd[0], &received_event, sizeof(event_t*));
                printf("read %d bytes\n", nbytes);
                if (nbytes > 0)
                    printf("Event id: %d\n", received_event->id);

                // Free the struct
                free(received_event);
            }
        }

        mywait(1); // sleep thread
    }

    return 0;
}

// From http://somethingswhichidintknow.blogspot.com/
// 2009/09/sleep-in-pthread.html
pthread_mutex_t fakeMutex = PTHREAD_MUTEX_INITIALIZER;
pthread_cond_t fakeCond = PTHREAD_COND_INITIALIZER;

void mywait(int timeInSec)
{
    struct timespec timeToWait;
    struct timeval now;
    int rt;
    gettimeofday(&now,NULL);

    timeToWait.tv_sec = now.tv_sec + timeInSec;
    timeToWait.tv_nsec = now.tv_usec*1000;

    pthread_mutex_lock(&fakeMutex);
    rt = pthread_cond_timedwait(&fakeCond, &fakeMutex, &timeToWait);
    pthread_mutex_unlock(&fakeMutex);
}