平台信息:
内核：linux3.1.0
系统：android5.0
平台：tiny4412
作者：庄泽彬(欢迎转载，请注明作者)
说明: 韦老师的安卓视频学习笔记
一、在一个进程中多个线程如何进行通信，主要使用的是socketpair的机制，详细代码如下:
1 #include <pthread.h> 2 #include <unistd.h> 3 #include <stdio.h> 4 #include <sys/types.h> /* See NOTES */ 5 #include <sys/socket.h> 6 7 8 #define SOCKET_BUFFER_SIZE (32768U) 9 #define BUF_MAX_LEN 512 10 11 void *function_thread (void *arg) 12 { 13 int fd = (int)arg; 14 char buf[BUF_MAX_LEN]; 15 int cnt = 0; 16 int len = -1; 17 18 19 while(1) 20 { 21 len = sprintf(buf,"Hello,main thread1, cnt = %d ",cnt++); 22 write(fd,buf,len); 23 24 len = read(fd,buf,BUF_MAX_LEN); 25 buf[len] = ' '; 26 printf("thead1 read:%s ",buf); 27 28 sleep(5); 29 } 30 31 32 return NULL; 33 } 34 35 36 int main(int argc,char **argv) 37 { 38 int ret = -1; 39 int sockets[2]; 40 int bufferSize = SOCKET_BUFFER_SIZE; 41 pthread_t threadID; 42 char buf[BUF_MAX_LEN]; 43 int len = 0; 44 int cnt = 0; 45 int fd = -1; 46 47 ret = socketpair(AF_UNIX,SOCK_SEQPACKET,0,sockets); 48 if(ret){ 49 printf("Error socketpair "); 50 return -1; 51 } 52 53 setsockopt(sockets[0], SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize)); 54 setsockopt(sockets[0], SOL_SOCKET, SO_RCVBUF, &bufferSize, sizeof(bufferSize)); 55 setsockopt(sockets[1], SOL_SOCKET, SO_SNDBUF, &bufferSize, sizeof(bufferSize)); 56 setsockopt(sockets[1], SOL_SOCKET, SO_RCVBUF, &bufferSize, sizeof(bufferSize)); 57 58 ret = pthread_create(&threadID,NULL,function_thread,(void *)sockets[1]); 59 60 fd = sockets[0]; 61 62 while(1){ 63 len = read(fd,buf,BUF_MAX_LEN); 64 buf[len] = ' '; 65 printf("Main thread read:%s ",buf); 66 67 len = sprintf(buf,"Hello,thread1, cnt = %d ",cnt++); 68 write(fd,buf,len); 69 } 70 71 return 0; 72 }
编译方法:gcc -o socketpair socketpair.c -lpthread
二、实验现象:
三、如下图所示socketpair的进程号为5919,在这个进程下面有两个线程运行。
