mkfifo /tmp/mplayer-input
 mplayer -slave -idle -input file=/tmp/mplayer-input abc.avi
 echo pause >/tmp/mplayer-input
Thanks, Cedric!
That would have been my approach to the problem, just like writing
"system(" to the beginning of each line... I really think I should learn C
one day...
Greets,
Kiste