linux 線程或進程之間通過管道通訊（pipe）

線程間通訊：

#include <stdio.h>  // printf#include <stdlib.h> // exit#include <unistd.h> // pipe#include <string.h> // strlen#include <pthread.h> // pthread_createusing namespace std;void *func(void * fd){        printf("write fd = %d\n", *(int*)fd);        char str[] = "hello everyone!";        write( *(int*)fd, str, strlen(str) );}int main(){        int fd[2];        char readbuf[1024];        if(pipe(fd) < 0)        {                printf("pipe error!\n");        }        // create a new thread        pthread_t tid = 0;        pthread_create(&tid, NULL, func, &fd[1]);        pthread_join(tid, NULL);        sleep(3);        // read buf from child thread        read( fd[0], readbuf, sizeof(readbuf) );        printf("read buf = %s\n", readbuf);        return 0;}

// 輸出結果

write fd = 4read buf = hello everyone!�

處理序間通訊：

#include <stdio.h>  // printf#include <stdlib.h> // exit#include <unistd.h> // pipe#include <string.h> // strlen#include <pthread.h> // pthread_createusing namespace std;int main(){        int fd[2];        int pid = 0;        char str[] = "hello";        char readbuf[1024];        if(pipe(fd) < 0)        {                printf("pipe error!\n");        }        if((pid = fork()) < 0)        {                printf("fork error!\n");        }        else if(pid == 0)        {                printf("child process!\n");                // close read channel                close(fd[0]);                write(fd[1], str, strlen(str));        }        else        {                printf("father process!\n");                // close write channel                close(fd[1]);                read(fd[0], readbuf, sizeof(readbuf));                printf("readbuf = %s\n", readbuf);        }        return 0;}

// 輸出結果：

father process!child process!readbuf = hello