Enter command (? for help)> s
invalid command
Enter command (? for help)> s b@dfilename
invalid command
Enter command (? for help)> s bad filename
invalid command
Enter command (? for help)> s   ok_filename
no images to save
Enter command (? for help)> l
invalid command
Enter command (? for help)> l b@dfilename
invalid command
Enter command (? for help)> l bad filename
invalid command
Enter command (? for help)> l   ok_filename
Enter command (? for help)> a
invalid command
Enter command (? for help)> a b@d.image
invalid command
Enter command (? for help)> a bad image
invalid command
Enter command (? for help)> a   _.ok._
--> _.ok._ [0] <--
    _.ok._ [0]
Enter command (? for help)> s
invalid command
Enter command (? for help)> s b@dfilename
invalid command
Enter command (? for help)> s bad filename
invalid command
Enter command (? for help)> s   ok_filename
warning: file already exists, will be overwritten
Enter command (? for help)> j
invalid command
Enter command (? for help)> j ten
invalid command
Enter command (? for help)> j   10
--> _.ok._ [0] <--
    _.ok._ [0]
Enter command (? for help)> j   -10
--> _.ok._ [0] <--
    _.ok._ [0]
Enter command (? for help)> u
invalid command
Enter command (? for help)> u ten
invalid command
Enter command (? for help)> u 0
invalid command
Enter command (? for help)> u -1
invalid command
Enter command (? for help)> u    1
--> _.ok._ [1] <--
    _.ok._ [0]
Enter command (? for help)> i
invalid command
Enter command (? for help)> i b@d.image
invalid command
Enter command (? for help)> i bad image
invalid command
Enter command (? for help)> i   __..ok..__
    _.ok._ [0]
--> __..ok..__ [0] <--
    _.ok._ [1]
Enter command (? for help)> c
invalid command
Enter command (? for help)> c b@d
invalid command
Enter command (? for help)> c bad search
invalid command
Enter command (? for help)> c   a
not found
Enter command (? for help)> c _.
    __..ok..__ [0]
--> _.ok._ [1] <--
    _.ok._ [0]
Enter command (? for help)> x
exit