Python 3 os.pipe()用法及代碼示例

描述

方法pipe()創建一個管道並返回一對分別可用於讀取和寫入的文件描述符 (r, w)

用法

以下是語法pipe()方法≫

os.pipe()

參數

NA

返回值

此方法返回一對文件描述符。

示例

下麵的例子展示了 pipe() 方法的用法。

#!/usr/bin/python3
import os, sys

print ("The child will write text to a pipe and ")
print ("the parent will read the text written by child...")

# file descriptors r, w for reading and writing
r, w = os.pipe() 

processid = os.fork()
if processid:
   # This is the parent process 
   # Closes file descriptor w
   os.close(w)
   r = os.fdopen(r)
   print ("Parent reading")
   str = r.read()
   print ("text =", str   )
   sys.exit(0)
else:
   # This is the child process
   os.close(r)
   w = os.fdopen(w, 'w')
   print ("Child writing")
   w.write("Text written by child...")
   w.close()
   print ("Child closing")
   sys.exit(0)

結果

當我們運行上麵的程序時，它會產生以下結果——

The child will write text to a pipe and 
the parent will read the text written by child...
Parent reading
('text =', 'Text written by child...')
The child will write text to a pipe and 
the parent will read the text written by child...
Child writing
Child closing.