我如何传递一个字符串到子进程。Popen(使用stdin参数)?

如果我这样做:

import subprocess
from cStringIO import StringIO
subprocess.Popen(['grep','f'],stdout=subprocess.PIPE,stdin=StringIO('one\ntwo\nthree\nfour\nfive\nsix\n')).communicate()[0]

我得到:

Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/build/toolchain/mac32/python-2.4.3/lib/python2.4/subprocess.py", line 533, in __init__
    (p2cread, p2cwrite,
  File "/build/toolchain/mac32/python-2.4.3/lib/python2.4/subprocess.py", line 830, in _get_handles
    p2cread = stdin.fileno()
AttributeError: 'cStringIO.StringI' object has no attribute 'fileno'

显然是cStringIO。StringIO对象的嘎嘎声不够接近文件鸭子，不适合subprocess.Popen。我怎么解决这个问题呢?

当前回答

from subprocess import Popen, PIPE
from tempfile import SpooledTemporaryFile as tempfile
f = tempfile()
f.write('one\ntwo\nthree\nfour\nfive\nsix\n')
f.seek(0)
print Popen(['/bin/grep','f'],stdout=PIPE,stdin=f).stdout.read()
f.close()

2012-04-13 03:36:37

其他回答

在Python 3.7+上这样做:

my_data = "whatever you want\nshould match this f"
subprocess.run(["grep", "f"], text=True, input=my_data)

并且您可能希望添加capture_output=True以获得以字符串形式运行命令的输出。

在旧版本的Python中，将text=True替换为universal_newlines=True:

subprocess.run(["grep", "f"], universal_newlines=True, input=my_data)

2019-12-27 04:29:04

我使用python3，发现你需要编码你的字符串，然后才能将它传递到stdin:

p = Popen(['grep', 'f'], stdout=PIPE, stdin=PIPE, stderr=PIPE)
out, err = p.communicate(input='one\ntwo\nthree\nfour\nfive\nsix\n'.encode())
print(out)

2014-07-27 15:29:17

p = Popen(['grep', 'f'], stdout=PIPE, stdin=PIPE, stderr=STDOUT)    
p.stdin.write('one\n')
time.sleep(0.5)
p.stdin.write('two\n')
time.sleep(0.5)
p.stdin.write('three\n')
time.sleep(0.5)
testresult = p.communicate()[0]
time.sleep(0.5)
print(testresult)

2009-04-09 04:39:40

显然是cStringIO。StringIO对象的嘎嘎声不够接近适合子进程的文件鸭。Popen

恐怕不行。管道是一个低级的操作系统概念，因此它绝对需要一个由操作系统级文件描述符表示的文件对象。你的解决方法是正确的。

2008-10-02 18:33:23

from subprocess import Popen, PIPE
from tempfile import SpooledTemporaryFile as tempfile
f = tempfile()
f.write('one\ntwo\nthree\nfour\nfive\nsix\n')
f.seek(0)
print Popen(['/bin/grep','f'],stdout=PIPE,stdin=f).stdout.read()
f.close()

2012-04-13 03:36:37

我如何传递一个字符串到子进程。Popen(使用stdin参数)?

推荐文章

最新文章

标签