Remove the last remains of slave mode

Almost nothing was left of it.

The only thing this commit actually removes is support for reading
input commands from stdin. But you can emulate this via:

 --input-file=/dev/stdin --input-terminal=no

However, this won't work on Windows. Just use a named pipe.

2 files changed, 10 insertions, 32 deletions

diff --git a/DOCS/man/changes.rst b/DOCS/man/changes.rst
index f1f336ac7c..df6fe9adef 100644
--- a/DOCS/man/changes.rst
+++ b/DOCS/man/changes.rst
@@ -308,28 +308,28 @@ input.conf and Slave Commands
 Slave mode
 ~~~~~~~~~~
 
-* Slave mode is broken. This mode is entirely insane in the ``old`` versions of
-  MPlayer. A proper slave mode application needed tons of code and hacks to get
+* Slave mode was removed. A proper slave mode application needed tons of code
+  and hacks to get
   it right. The main problem is that slave mode is a bad and incomplete
   interface, and to get around that, applications parsed output messages
   intended for users. It is hard to know which messages exactly are parsed by
   slave mode applications. This makes it virtually impossible to improve
   terminal output intended for users without possibly breaking something.
 
-  This is absolutely insane, and **mpv** will not try to keep slave mode
-  compatible. If you are a developer of a slave mode application, contact us,
-  and a new and better protocol can be developed.
+  This is absolutely insane, and since initial improvements to **mpv** quickly
+  made slave mode incompatible to most applications, it was removed as useless
+  cruft. The client API (see below) is provided instead.
 
-  ``--identify`` was already removed (``TOOLS/mpv_identify.sh`` is provided
-  instead), and ``--slave-broken`` might be removed in the future.
+  ``--identify`` was replaced by the ``TOOLS/mpv_identify.sh`` wrapper script.
+
+* A JSON RPC protocol giving access to the client API is planned, but nothing
+  has emerged yet.
 
 * **mpv** also provides a client API, which can be used to embed the player
   by loading it as shared library. (See ``libmpv/client.h`` in the sources.)
   It might also be possible to implement a custom slave mode-like protocol
   using Lua scripting.
 
-* A slave protocol is planned, but nothing has emerged yet.
-
 Policy for Removed Features
 ---------------------------
 
diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst
index 9f67523f66..e3cef52f99 100644
--- a/DOCS/man/options.rst
+++ b/DOCS/man/options.rst
@@ -1191,8 +1191,7 @@ OPTIONS
 
 ``--idle``
     Makes mpv wait idly instead of quitting when there is no file to play.
-    Mostly useful in slave mode, where mpv can be controlled through input
-    commands (see also ``--slave-broken``).
+    Useful with ``--force-window``, or for client API.
 
 ``--index=<mode>``
     Controls how to seek in files. Note that if the index is missing from a
@@ -1252,7 +1251,6 @@ OPTIONS
 
 ``--input-file=<filename>``
     Read commands from the given file. Mostly useful with a FIFO.
-    See also ``--slave-broken``.
 
     .. note::
 
@@ -2102,24 +2100,6 @@ OPTIONS
         - ``mpv --slang=jpn example.mkv`` plays a Matroska file with Japanese
           subtitles.
 
-``--slave-broken``
-    Switches on the old slave mode. This is for testing only, and incompatible
-    to the removed ``--slave`` switch.
-
-    .. attention::
-        Changes incompatible to slave mode applications have been made. In
-        particular, the status line output was changed, which is used by some
-        applications to determine the current playback position. This switch
-        has been renamed to prevent these applications from working with this
-        version of mpv, because it would lead to buggy and confusing behavior
-        only. Moreover, the slave mode protocol is so horribly bad that it
-        should not be used for new programs, nor should existing programs
-        attempt to adapt to the changed output and use the ``--slave-broken``
-        switch. Instead, a new, saner protocol should be developed (and will be,
-        if there is enough interest).
-
-        This affects most third-party GUI frontends.
-
 ``--softsleep``
     Time frames by repeatedly checking the current time instead of asking
     the kernel to wake up mpv at the correct time. Useful if your kernel
@@ -2860,8 +2840,6 @@ OPTIONS
     as parent. The window will always be resized to cover the parent window
     fully, and will add black bars to compensate for the video aspect ratio.
 
-    See also ``--slave-broken``.
-
 ``--no-window-dragging``
     Don't move the window when clicking on it and moving the mouse pointer.