一个简单的聊天程序--命名管道FIFO

本程序是一个使用FIFO进行进程间通信的典型程序lucy.c创建了FIFO write──fifo用于向程序peter.c发送信息：程序创建了FIFO read-fifo，用于向lucy.c发送消息。编译本程序，先运行peter.c再运行lucy.c就可以了。

源程序如下：

//filename:lucy.c

#include<sys/types.h>

#include<sys/stat.h>

#include<string.h>

#include<stdio.h>

#include<errno.h>

#include<fcntl.h>

#include<unistd.h>

#include<stdlib.h>

int main(viod)

{

char write_fifo_name[]="write-fifo";

char read_fifo_name[]="read-fifo";

int write_fd,read_fd;

char buf[256];

int len;

struct stat_buf;



int ret=mkfifo(write_fifo_name,S_IRUSR | S_IWUSR);

if(ret==-1)

{printf("failed to create FIFO %s:%s\n",write_fifo_name,strerror(errno));

exit(-1);

}



write_fd=open(write_fifo_name,O_WRONLY);

if(write_fd==-1)

{printf("failed to open FIFO %s:%s\n",write_fifo_name,strerror(errno));

exit(-1);}



while((read_fd=open(read_fifo_name,O_RDONLY))==-1)

{sleep(1);}



while(1){printf("lucy:");

fgets(buf,256,stdin);

buf[strlen(buf)-1]='\0';

if(strncmp(buf,"quit",4)==0)

{close(write_fd);

unlink(write_fifo_name);

close(read_fd);

exit(0);

}

write(write_fd,buf,strlen(buf));

len=read(read_fd,buf,256);

if(len>0)

{

buf[len]='\0';

printf("perter:%s\n",buf);

}

}

}

//filename:peter.c

#include<sys/types.h>

#include<sys/stat.h>

#include<string.h>

#include<stdio.h>

#include<errno.h>

#include<fcntl.h>

#include<unistd.h>

#include<stdlib.h>

int main(viod)

{

char write_fifo_name[]="read-fifo";

char read_fifo_name[]="write-fifo";

int write_fd,read_fd;

char buf[256];

int len;

//struct stat_buf;



int ret=mkfifo(write_fifo_name,S_IRUSR | S_IWUSR);

if(ret==-1)

{

printf("failed to create FIFO %s:%s\n",write_fifo_name,strerror(errno));

exit(-1);

}

while((read_fd=open(read_fifo_name,O_RDONLY))==-1)

{

sleep(1);

}



write_fd=open(write_fifo_name,O_WRONLY);

if(write_fd==-1)

{

printf("failed to open FIFO %s:%s\n",write_fifo_name,strerror(errno));

exit(-1);

}





while(1)

{

len=read(read_fd,buf,256);

if(len>0)

{

buf[len]='\0';

printf("lucy:%s\n",buf);

}

printf("peter:");

fgets(buf,256,stdin);

buf[strlen(buf)-1]='\0';

if(strncmp(buf,"quit",4)==0)

{

close(write_fd);

unlink(write_fifo_name);

close(read_fd);

exit(0);

}

write(write_fd,buf,strlen(buf));

}

}