#1727024: document that Popen.returncode is set by Popen.poll/wait.

This commit is contained in:
Georg Brandl 2008-01-06 16:01:26 +00:00
parent c4768a4a98
commit 2cb103ffa9
1 changed files with 15 additions and 10 deletions

View File

@ -178,12 +178,14 @@ Instances of the :class:`Popen` class have the following methods:
.. method:: Popen.poll()
Check if child process has terminated. Returns returncode attribute.
Check if child process has terminated. Set and return :attr:`returncode`
attribute.
.. method:: Popen.wait()
Wait for child process to terminate. Returns returncode attribute.
Wait for child process to terminate. Set and return :attr:`returncode`
attribute.
.. method:: Popen.communicate(input=None)
@ -193,21 +195,21 @@ Instances of the :class:`Popen` class have the following methods:
*input* argument should be a string to be sent to the child process, or
``None``, if no data should be sent to the child.
communicate() returns a tuple (stdout, stderr).
:meth:`communicate` returns a tuple ``(stdout, stderr)``.
Note that if you want to send data to the process's stdin, you need to create
the Popen object with ``stdin=PIPE``. Similarly, to get anything other than
``None`` in the result tuple, you need to give ``stdout=PIPE`` and/or
``stderr=PIPE`` too.
.. note::
.. note::
The data read is buffered in memory, so do not use this method if the data
size is large or unlimited.
The data read is buffered in memory, so do not use this method if the data size
is large or unlimited.
The following attributes are also available:
.. attribute:: Popen.stdin
If the *stdin* argument is ``PIPE``, this attribute is a file object that
@ -233,9 +235,12 @@ The following attributes are also available:
.. attribute:: Popen.returncode
The child return code. A ``None`` value indicates that the process hasn't
terminated yet. A negative value -N indicates that the child was terminated by
signal N (Unix only).
The child return code, set by :meth:`poll` and :meth:`wait` (and indirectly
by :meth:`communicate`). A ``None`` value indicates that the process
hasn't terminated yet.
A negative value ``-N`` indicates that the child was terminated by signal
``N`` (Unix only).
Replacing Older Functions with the subprocess Module