Merge from origin/emacs-26

df64da8 (origin/emacs-26) * lisp/simple.el (region-extract-function):...
520c486 * lisp/simple.el (region-bounds): Doc fix.  (Bug#33168)
9193db0 Improve documentation of 'process-connection-type'
106b9e1 Unify prompt for gnupg passphrase between GNU/Linux and MS-Wi...
2a41616 Doc fix of 'gnus-fetch-old-headers'
29a7644 Deactivate incorrect hyperlinking in gnus-build-sparse-thread...
53ae90f Minor copyedits in cmdargs.texi
fc2e65a Improve documentation of X resource loading
13132b3 * lisp/net/tramp-sh.el (tramp-inline-compress-commands):
8361292 ; Fix sorting in admin/MAINTAINERS
92de44f Don't error when indenting malformed Lisp (Bug#30891)
c3adbc8 Improve 'isearch-delete-char' documentation (Bug#32990)
6ca71ce ; * lisp/help.el (with-help-window): Remove extra space in doc.
f5f9583 Improve XPM load failure message (bug#33126)
f3d01d4 Avoid infloop in CPerl mode fontification
71a2d50 Fix minibuffer-help-form for lexical binding
7e8eee6 Fix some NS drawing issues (bug#32932)
d72975a * lisp/gnus/mm-util.el (mm-decompress-buffer): Fix split-stri...
c97a5f1 * doc/misc/calc.texi (Summary): The +/- key is 'p', not 'P'.

# Conflicts:
#	lisp/gnus/mm-util.el

1 files changed, 12 insertions, 7 deletions

diff --git a/doc/lispref/processes.texi b/doc/lispref/processes.texi
index e1113e37f10..2afc6a33828 100644
--- a/doc/lispref/processes.texi
+++ b/doc/lispref/processes.texi
@@ -598,8 +598,8 @@ communication is only partially asynchronous: Emacs sends data to the
 process only when certain functions are called, and Emacs accepts data
 from the process only while waiting for input or for a time delay.
 
-@cindex pty
-@cindex pipe
+@cindex pty, when to use for subprocess communications
+@cindex pipe, when to use for subprocess communications
   An asynchronous process is controlled either via a @dfn{pty}
 (pseudo-terminal) or a @dfn{pipe}.  The choice of pty or pipe is made
 when creating the process, by default based on the value of the
@@ -609,11 +609,13 @@ Shell mode, because they allow for job control (@kbd{C-c}, @kbd{C-z},
 etc.)@: between the process and its children, and because interactive
 programs treat ptys as terminal devices, whereas pipes don't support
 these features.  However, for subprocesses used by Lisp programs for
-internal purposes, it is often better to use a pipe, because pipes are
+internal purposes (i.e., with no user interaction), where significant
+amounts of data need to be exchanged between the subprocess and the
+Lisp program, it is often better to use a pipe, because pipes are
 more efficient, and because they are immune to stray character
 injections that ptys introduce for large (around 500 byte) messages.
-Also, the total number of ptys is limited on many systems and it is
-good not to waste them.
+Also, the total number of ptys is limited on many systems, and it is
+good not to waste them unnecessarily.
 
 @defun make-process &rest args
 This function is the basic low-level primitive for starting
@@ -666,7 +668,9 @@ pipe, or @code{nil} to use the default derived from the value of the
 @code{process-connection-type} variable.  This parameter and the value
 of @code{process-connection-type} are ignored if a non-@code{nil}
 value is specified for the @code{:stderr} parameter; in that case, the
-type will always be @code{pipe}.
+type will always be @code{pipe}.  On systems where ptys are not
+available (MS-Windows), this parameter is likewise ignored, and pipes
+are used unconditionally.
 
 @item :noquery @var{query-flag}
 Initialize the process query flag to @var{query-flag}.
@@ -873,7 +877,8 @@ around the call to these functions.
 Note that the value of this variable is ignored when
 @code{make-process} is called with a non-@code{nil} value of the
 @code{:stderr} parameter; in that case, Emacs will communicate with
-the process using pipes.
+the process using pipes.  It is also ignored if ptys are unavailable
+(MS-Windows).
 
 @smallexample
 @group