pipes
— Shell 管道接口
¶
源代码： Lib/pipes.py
Deprecated since version 3.11, will be removed in version 3.13:
pipes
模块被弃用 (见
PEP 594
for details). Please use the
subprocess
模块代替。
pipes
module defines a class to abstract the concept of a
pipeline
— a sequence of converters from one file to another.
Because the module uses
/bin/sh
command lines, a POSIX or compatible shell for
os.system()
and
os.popen()
被要求。
可用性 : Unix, not VxWorks.
pipes
模块定义了下列类：
An abstraction of a pipeline.
范例：
>>> import pipes >>> t = pipes.Template() >>> t.append('tr a-z A-Z', '--') >>> f = t.open('pipefile', 'w') >>> f.write('hello world') >>> f.close() >>> open('pipefile').read() 'HELLO WORLD'
Template objects following methods:
Restore a pipeline template to its initial state.
Return a new, equivalent, pipeline template.
若
flag
is true, turn debugging on. Otherwise, turn debugging off. When debugging is on, commands to be executed are printed, and the shell is given
set -x
command to be more verbose.
Append a new action at the end. The cmd variable must be a valid bourne shell command. The kind variable consists of two letters.
The first letter can be either of
'-'
(which means the command reads its standard input),
'f'
(which means the commands reads a given file on the command line) or
'.'
(which means the commands reads no input, and hence must be first.)
Similarly, the second letter can be either of
'-'
(which means the command writes to standard output),
'f'
(which means the command writes a file on the command line) or
'.'
(which means the command does not write anything, and hence must be last.)
Add a new action at the beginning. See
append()
for explanations of the arguments.
Return a file-like object, open to
file
, but read from or written to by the pipeline. Note that only one of
'r'
,
'w'
may be given.
拷贝 infile to outfile through the pipe.