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标题: linux中FIFO实现一个服务器多个客户 [打印本页]

作者: _Gushi 时间: 2018-07-24 20:04
标题: linux中FIFO实现一个服务器多个客户

//server.c
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "my_err.h"
#include "unpipc.h"

#define SERV_FIFO "/work/test/test.serv"

int main()
{
      char buff[MAXLINE+1],fifoname[MAXLINE];

      if((mkfifo(SERV_FIFO,FILE_MODE)<0)&&(errno!=EEXIST))
      err_sys("can't create %s",SERV_FIFO);

      //open sever's well-know FIFO reading and write
      int readfifo=open(SERV_FIFO,O_RDONLY,0);
      int dummyfd=open(SERV_FIFO,O_WRONLY,0);

      //read pathname from IPC(is from client pathname) to fifoname
      ssize_t n;
      if((n=read(readfifo,fifoname,MAXLINE))==0)
            err_quit("end of file while reading pathname");
      //fifoname[n]='\0';

      //open write text to pathname(fifoname)
      int writefd=open(fifoname,O_WRONLY,0);

      //write text(from SERV_FIFO) to pathname(fifoname)
      int fd;
      if((fd=open(fifoname,O_RDONLY))<0)
      {
            int len=strlen(fifoname);
            write(writefd,fifoname,len);
            close(writefd);
      }
      else
      {
            while((n=read(fd,buff,MAXLINE))>0)
                     write(writefd,buff,n);

            close(fd);
            close(writefd);
      }
      exit(0);
}

//client.c
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include "unpipc.h"
#include "my_err.h"

#define SERV_FIFO "/work/test/test.serv"

int main()
{
      char fifoname[MAXLINE],buff[MAXLINE];

      //read pathname
      fgets(fifoname,MAXLINE,stdin);
      size_t len=strlen(fifoname);
      if(fifoname[len]=='\n')
      len--;

      //create FIFO whie pathname
      if((mkfifo(fifoname,FILE_MODE)<0)&&(errno!=EEXIST))
      err_sys("can't create %s",fifoname);

      //open FIFO to server and write pathname to FIFO
      int writefifo=open(SERV_FIFO,O_WRONLY,0);
      write(writefifo,fifoname,len);

      //now open our FIFO;blocks until server opens for writing
      int readfifo=open(fifoname,O_RDONLY,0);

      //read from IPC,write to standard output
      ssize_t n;
      while((n=read(readfifo,buff,MAXLINE))>0)
      write(STDOUT_FILENO,buff,n);

      close(readfifo);
      unlink(fifoname);
      exit(0);
}
运行完./server &后，运行./client，gdb调试时总是阻塞在int readfifo=open(fifoname,O_RDONLY,0);，求指教。

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