主题：进程的管道通信



内容：这是一个设计型实验，要求自行编制程序。

使用系统调用pipe()建立一条管道，两个子进程分别向管道写一句话：

Child process1 is sending a message!

Child process2 is sending a message!

父进程从管道读出来自两个子进程的信息，显示在屏幕上。

要求：

1）　　父进程先接收子进程1发来的消息，然后再接收子进程2发来的消息。

2）　　实现管道的互斥使用,当一个子进程正在对管道进行写操作时，另一子进程必须等待。使用系统调用lockf(fd[1],1,0)实现对管道的加锁操作，用lockf(fd[1],0,0)解除对管道的锁定。

3）　　实现父子进程的同步，当子进程把数据写入管道后，便去睡

-Topic: process piping communication



Content: this is a design model experiment, the requirement to programming.

Use system call pipe () to establish a pipe, two sons to write a process piping,

Money is a macro was not found process1 delivery!

Money is a macro was not found process2 delivery!

The parent process piping from two read from the process of information displayed on a screen.

Requirements:

1) parent to receive the messages from one child processes, and then receive child processes of 2.

2 the exclusive use of tube), when a child processes are for write operation, another child processes must wait. Use the system calls lockf (fd [1], 1,0) of the pipeline, lockf with lock (fd [1] on pipeline, 0,0) of the lock.

3) the synchronous process, and the data into the child process piping, then go to sleep