* doc/lispref/processes.texi (Network): Document non-string
capability command.
* lisp/gnus/nntp.el (nntp-open-connection): Use HELP for Typhoon
and CAPABILITIES for everything else (bug#41960).

* lisp/net/network-stream.el (open-network-stream): Document
function variety of :capability-command.
(network-stream-open-starttls): Use it.
(network-stream-open-tls): Ditto.
(network-stream-open-shell): Ditto.
(network-stream--capability-command): New helper function.

* doc/lispref/processes.texi (Synchronous Processes):
Describe `process-file-return-signal-string'.

* doc/misc/tramp.texi: Adapt Tramp and Emacs version numbers.
(Remote processes): Describe `process-file-return-signal-string'
and $INSIDE_EMACS.

* etc/NEWS: Describe `process-file-return-signal-string'.  Fix typos.

* lisp/simple.el (process-file-return-signal-string): New user option.

* lisp/net/tramp-adb.el (tramp-adb-handle-process-file):
* lisp/net/tramp-sh.el (tramp-sh-handle-process-file): Use it.

* lisp/net/tramp.el (tramp-get-signal-strings): New defun.

* test/lisp/net/tramp-tests.el (tramp-test28-process-file): Adapt test.

* doc/lispref/processes.texi (Network): Describe :coding keyword support.

* doc/misc/emacs-gnutls.texi (Help For Developers): Describe :coding
keyword support.

* etc/NEWS: Announce change to open-network-stream and
open-gnutls-stream.

* lisp/net/gnutls.el (open-gnutls-stream): Add support for :coding, pass it
down to open-network-stream.

* lisp/net/network-stream.el (open-network-stream)
(network-stream-open-plain, network-stream-open-starttls): Add
support for :coding, pass it down to make-network-process.
(network-stream-open-shell): Add support-for :coding, use
set-process-coding-system to set it after process creation.

A common complaint about the module API is that modules can't
communicate asynchronously with Emacs.  While it isn't possible to
call arbitrary Emacs functions asynchronously, writing to a pipe
should always be fine and is a pretty low-hanging fruit.

This patch implements a function that adapts an existing pipe
process.  That way, users can use familiar tools like process filters
or 'accept-process-output'.

* src/module-env-28.h: Add 'open_channel' module function.

* src/emacs-module.c (module_open_channel): Provide definition for
'open_channel'.
(initialize_environment): Use it.

* src/process.c (open_channel_for_module): New helper function.
(syms_of_process): Define necessary symbol.

* test/src/emacs-module-tests.el (module/async-pipe): New unit test.

* test/data/emacs-module/mod-test.c (signal_system_error): New helper
function.
(signal_errno): Use it.
(write_to_pipe): New function running in the background.
(Fmod_test_async_pipe): New test module function.
(emacs_module_init): Export it.

* doc/lispref/internals.texi (Module Misc): Document new module
function.

* doc/lispref/processes.texi (Asynchronous Processes): New anchor
for pipe processes.

* etc/NEWS: Document 'open_channel' function.

* doc/emacs/cmdargs.texi (General Variables):
* doc/lispintro/emacs-lisp-intro.texi (Lisp History):
* doc/lispref/processes.texi (Network):
* doc/misc/gnus-coding.texi (Gnus Coding Style):
* doc/misc/gnus.texi (Oort Gnus):
* doc/misc/smtpmail.texi (Encryption): Remove references to obsolete
libraries.  (Bug#37964)

Run "TZ=UTC0 admin/update-copyright $(git ls-files)".

Bug#38218

* src/process.c (Fnetwork_interface_list): Extend argument list to
allow requesting full network info and/or IPv4/IPv6 info.
(network_interface_list) [HAVE_GETIFADDRS]: Use getifaddrs to retrieve
interface IP addresses.

* src/process.h: Update prototype of network_interface_list.

* src/w32.c (g_b_init_get_adapters_addresses): New init flag.
(globals_of_w32): Initialize it.
(GetAdaptersAddresses_Proc): New function typedef.
(get_adapters_addresses): New wrapper function.
(init_winsock): Load htonl and ntohl.
(sys_htonl, sys_ntohl): New wrapper functions.
(network_interface_list): Implement in terms of
get_adapters_addresses.

* nt/inc/sys/socket.h: Add sys_htonl and sys_ntohl prototypes.

* etc/NEWS: Announce IPv4/IPv6 changes in network-interface-list.

* doc/lispref/processes.texi (Misc Network): Document updated arglist
and return values for network-interface-list.

* lisp/net/network-stream.el (network-stream-use-client-certificates):
Default to nil.
(open-network-stream): Adapt description to new default of
network-stream-use-client-certificates.

* etc/NEWS: network-stream-use-client-certificates defaults to nil
now.

* doc/lispref/processes.texi (Network): Flip
network-stream-use-client-certificates description.

* doc/misc/auth.texi (Help for users): Mention
network-stream-use-client-certificates.