[Python-checkins] bpo-40094: Enhance os.WIFEXITED documentation (GH-19244) (GH-19278)

[Miss Islington (bot)]

https://github.com/python/cpython/commit/c8dd641b6214bdcf794bab469a51da6843feb770
commit: c8dd641b6214bdcf794bab469a51da6843feb770
branch: 3.7
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: GitHub <noreply at github.com>
date: 2020-04-02T01:26:47+02:00
summary:

bpo-40094: Enhance os.WIFEXITED documentation (GH-19244) (GH-19278)

(cherry picked from commit 7c72383f95b0cdedf390726069428d7b69ed2597)

Co-authored-by: Victor Stinner <vstinner at python.org>

files:
M Doc/library/os.rst

diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index e23500d43391f..685d5608f7fbf 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -3765,28 +3765,36 @@ used to determine the disposition of a process.
    Return ``True`` if a core dump was generated for the process, otherwise
    return ``False``.
 
+   This function should be employed only if :func:`WIFSIGNALED` is true.
+
    .. availability:: Unix.
 
 
 .. function:: WIFCONTINUED(status)
 
-   Return ``True`` if the process has been continued from a job control stop,
-   otherwise return ``False``.
+   Return ``True`` if a stopped child has been resumed by delivery of
+   :data:`~signal.SIGCONT` (if the process has been continued from a job
+   control stop), otherwise return ``False``.
+
+   See :data:`WCONTINUED` option.
 
    .. availability:: Unix.
 
 
 .. function:: WIFSTOPPED(status)
 
-   Return ``True`` if the process has been stopped, otherwise return
-   ``False``.
+   Return ``True`` if the process was stopped by delivery of a signal,
+   otherwise return ``False``.
 
-   .. availability:: Unix.
+   :func:`WIFSTOPPED` only returns ``True`` if the :func:`waitpid` call was
+   done using :data:`WUNTRACED` option or when the process is being traced (see
+   :manpage:`ptrace(2)`).
 
+   .. availability:: Unix.
 
 .. function:: WIFSIGNALED(status)
 
-   Return ``True`` if the process exited due to a signal, otherwise return
+   Return ``True`` if the process was terminated by a signal, otherwise return
    ``False``.
 
    .. availability:: Unix.
@@ -3794,7 +3802,8 @@ used to determine the disposition of a process.
 
 .. function:: WIFEXITED(status)
 
-   Return ``True`` if the process exited using the :manpage:`exit(2)` system call,
+   Return ``True`` if the process exited terminated normally, that is,
+   by calling ``exit()`` or ``_exit()``, or by returning from ``main()``;
    otherwise return ``False``.
 
    .. availability:: Unix.
@@ -3802,8 +3811,9 @@ used to determine the disposition of a process.
 
 .. function:: WEXITSTATUS(status)
 
-   If ``WIFEXITED(status)`` is true, return the integer parameter to the
-   :manpage:`exit(2)` system call.  Otherwise, the return value is meaningless.
+   Return the process exit status.
+
+   This function should be employed only if :func:`WIFEXITED` is true.
 
    .. availability:: Unix.
 
@@ -3812,12 +3822,16 @@ used to determine the disposition of a process.
 
    Return the signal which caused the process to stop.
 
+   This function should be employed only if :func:`WIFSTOPPED` is true.
+
    .. availability:: Unix.
 
 
 .. function:: WTERMSIG(status)
 
-   Return the signal which caused the process to exit.
+   Return the number of the signal that caused the process to terminate.
+
+   This function should be employed only if :func:`WIFSIGNALED` is true.
 
    .. availability:: Unix.