A进程

#include <head.h>
int main(int argc, const char *argv[])
{pid_t cpid=fork();if(cpid>0)//父进程向管道文件2写{	int wfd;if((wfd=open("./myfifo2",O_WRONLY))==-1){ERR_MSG("open");return -1;}	char buf[128]="";while(1){bzero(buf,sizeof(buf));putchar(10);printf("B进程请输入:");fgets(buf,sizeof(buf),stdin);buf[strlen(buf)-1]=0;write(wfd,buf,sizeof(buf));if(strcmp(buf,"q")==0){printf("写进程退出\n");break;}}close(wfd);}else if(0==cpid)//子进程从管道文件1读取{int rfd;char buf1[128]="";if((rfd=open("./myfifo1",O_RDONLY))==-1){ERR_MSG("open");return -1;}while(1){bzero(buf1,sizeof(buf1));read(rfd,buf1,sizeof(buf1));if(strcmp(buf1,"q")==0){printf("写进程退出\n");break;}putchar(10);printf("A进程向B进程输出数据为%s\n",buf1);}close(rfd);}else {ERR_MSG("fork");return -1;}return 0;
}        

 

 B进程

#include <head.h>
int main(int argc, const char *argv[])
{pid_t cpid=fork();if(cpid>0)//父进程向管道文件1写{	int wfd;if((wfd=open("./myfifo1",O_WRONLY))==-1){ERR_MSG("open");return -1;}	char buf[128]="";while(1){bzero(buf,sizeof(buf));putchar(10);printf("A进程请输入");fgets(buf,sizeof(buf),stdin);buf[strlen(buf)-1]=0;write(wfd,buf,sizeof(buf));if(strcmp(buf,"q")==0){printf("写进程退出\n");break;}}close(wfd);}else if(0==cpid)//子进程从管道文件2读取{int rfd;char buf1[128]="";if((rfd=open("./myfifo2",O_RDONLY))==-1){ERR_MSG("open");return -1;}while(1){	int wfd;if((wfd=open("./myfifo1",O_WRONLY))==-1){ERR_MSG("open");return -1;}	char buf[128]="";bzero(buf1,sizeof(buf1));read(rfd,buf1,sizeof(buf1));if(strcmp(buf1,"q")==0){printf("写进程退出\n");break;}putchar(10);printf("B进程向A进程输出数据为%s\n",buf1);}close(rfd);}else {ERR_MSG("fork");return -1;}return 0;
}