os.pipe()関数はPythonで何をしますか?

Python Server-Side-Programming Programming

メソッドos.pipe()はパイプを作成し、それぞれ読み取りと書き込みに使用できるファイル記述子(r、w)のペアを返します。

 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()
# This is the parent process
if processid:
    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) 

出力

出力が得られます:

Parent reading
Child writing
Child closing
text = Text written by child...
2020-02-08 13:38
talonheavy
Avery Brown