程序三（进程间通信） ：创建管道，子进程向管道写信息，父进程从管道中读取信息。-Procedure three (inter-process communication): the creation of channels, sub-process to write information to the pipeline, the parent process read information the pipeline.

程序三（进程间通信） ：创建管道，子进程向管道写信息，父进程从管道中读取信息。-Procedure three (inter-process communication): the creation of channels, sub-process to write information to the pipeline, the parent process read information the pipeline.