choose one of the options below

for modifying files

edit 1	xterm -e vi bs.c &
edit 2	xterm -e vi bs.c &
edit 3	xterm -e vi bs.c &
edit 4	xterm -e vi bs.c &

for making programs

make 1	make
make 2	make
make 3	make


for testing them

run 1	bs i &
run 2	bs i &

then, when you are satisfied, try
