use a wildcard for the killall command to support current and legacy versions of retropie

[ds17f]

This PR addresses issue #82

The latest pre-made image of RetroPie, v4.6 – released April 28, 2020, has trouble with the shutdown script. It appears that the killall command fails because the emulationstation process is no longer identified by emulationstation but instead by its truncated, 15 character name, emulationstatio.
(see more here: https://linux.die.net/man/1/killall, specifically

If a command name is longer than 15 characters, the full name may be unavailable (i.e. it is swapped out).

I'm not entirely sure what brings about this change, but it's there none the less.

I first tried to use pkill to deal with this but the calling python script hangs and shutdown never occurs.

I next tried shortening the killall to killall emulationstatio, but this fails on my RetroPie 4.4 build which is my current daily driver.

In the end, I settled on using the -r flag and wildcarding any characters past the known 15 (emulationstatio). This works correctly on 4.6 and on 4.4.

[mmvanheusden]

test

[mmvanheusden]

i'm new on github

[mmvanheusden]

oops, Sorry

[ds17f]

I tried changing this file, rebooted the PI and it still isn't working. No matter if I press the power button off (its pushed in right now) or if I hit reset, nothing happens. The switch inside is ON.

I'm confused by your comment. You say "hit reset", I'm not sure what that means. This script is for the GPi, the Gameboy case. There is no "reset" button, only the switch at the top and the internal switch that enables safe shutdown.