Trying to fix my "custom music player" fish script

[walksanatora]

so i have the function

    function pl
        set -fx state_file (mktemp)
        function skip_handle -s USR1
            echo "state: $state_file"
        end
        function play_file -a file
            echo "state: $state_file"
            set ext (string split -r -m1 . {$file})[2]
            if test "$ext" = m3u
                for file2 in (cat $file | sort -R)
                    if test (string sub -l 1 $file2) = '@'
                        string sub -s 2 $file2 | xargs play
                    else
                        play_file "$file2"
                    end
                end
            else if test "$ext" = mp3 -o "$ext" = wav
                echo play >$state_file
                play "$file" &
                wait
            else if test "$ext" = xm
                echo xmp >$state_file
                xmp "$file" &
                wait
            end
        end
        set stop 0
        while test "$stop" = 0
            if test -n "$shuf"
                set argv (shuf -e (string collect $argv))
            end
            for file in $argv
                play_file "$file"
                if test -z "$loop"
                    set stop 1
                end
            end
        end
        #cleanup
        rm "$state_file"
        functions --erase skip_handle
        functions --erase play_file
    end

whenever I kill -10 <fish pid running this function> it does not print the status: because it is currently playing music (and the play command does not with when &'d)
only after the song finishes does it print the status:

[faho]

Fish does not currently support backgrounding functions. This is #238. If play is a function, your best bet is to instead call it as fish -c 'play $argv' $file &.

If it isn't, the issue is that nothing here has told it to react to the USR1 signal (that's number 10). What do you expect to react here? Fish has been signaled but it hasn't been told to do anything. So either send the signal to play, or add a --on-signal function that does something.

Or, alternatively, your actual best bet is to use a program built for the purpose - mpd with ncmpcpp might work for you.

[faho]

Okay, let's step back.

If you do play foo, without the &, then that means fish starts play and waits for it to exit. No fish signal handler function can run during.

If you do play foo &, that backgrounds play. Fish script can continue running, signal handlers can run.

But once you do wait, you're back to fish waiting for play to exit again.

Basically this idiom:

foo &
wait

is almost entirely useless. It's essentially the same as foo.

[walksanatora]

so then how should I properlly "start this program and wait for it to exit before starting the next loop while trapping signals"

[faho]

Currently: You don't. Fish script is entirely single-threaded so while something is running in the foreground signal handlers don't run.

Which is where I will point you towards trying a more capable music player again.

[walksanatora]

(and to think the entire reason I am doing this is so the python script I use to controll my music via keyboard keys+ mouse buttons (for when the lid is closed) can skip the tracker music... I could just make it so it is ~/.wmp-controll is a file)

[walksanatora]

i did the stupid ~/.wmp-controll and it works