Pause programmatically video player mpv

Question

I would like to know if there is a way to send a message to a running process on linux ?

For example, is it possible to programmatically "pause" a video launched with mpv.

Solution 1

To control mpv remotely (eg from another terminal session) you can also start it with the option

--input-ipc-server=/tmp/mpvsocket

and control it by issuing commands like this:

echo '{ "command": ["set_property", "pause", true] }' | socat - /tmp/mpvsocket

See man mpv for (many) more details.

edit: see also mpv --list-properties

edit2: The most simple way I've found to "toggle" pause/play is

{"command": ["cycle", "pause"]}

Solution 2

kill -s STOP $(pidof mpv) and kill -s CONT $(pidof mpv)

or better :

xdotool key --window "$(xdotool search --class mpv)" p

The key "P", is set by default to pause the video.

Solution 3

It's possible to control mpv through IPC. From the manual mpv(1):

--input-ipc-server=<filename>
       Enable the IPC support and create the listening socket at the given path.

       On  Linux and Unix, the given path is a regular filesystem path.
       On Windows, named pipes are used, so the path refers to the pipe namespace (\\.\pipe\<name>). If the \\.\pipe\ prefix is missing, mpv will add it automatically before creating the pipe, so --input-ipc-server=/tmp/mpv-socket and --input-ipc-server=\\.\pipe\tmp\mpv-socket are equivalent for IPC on Windows.

       See JSON IPC for details.

A couple of examples:

$ echo 'cycle pause'   | socat - /tmp/mpv-socket
$ echo 'playlist-prev' | socat - /tmp/mpv-socket
$ echo 'playlist-next' | socat - /tmp/mpv-socket

See mpv(1) to learn more.

See also:

• https://alexherbo2.github.io/blog/mpv/command-line-controller/
• https://gist.github.com/dwgill/a66769e0edef69c04d3b

Comments

[Wis]

with this option by default mpv creates a single socket, which is for the last mpv instance opened. to get multiple sockets per PID, use the mpvSockets plugin

[Sean Breckenridge]

Wish I had come across that plugin sooner o_o. Ended up writing my own solution to handle communicating with multiple IPC servers by using the epoch time to create multiple sockets.