at and batch read commands from standard input or a specified file which are to be executed at a later time, using /bin/sh. – man page
We can use at as an alarm clock
at now+5min
at> music123 /home/ian/Music/a.ogg
at> Ctrl-D
at 18:10
atq: list the at queue.
atrm: remove an at job.
music123 is a shell around various command line programs to play music files. You can install it by
% sudo apt-get install music123