input \"U)pload or D)ownload? "i$
 if i$="U" goto upload
 if i$<>"D" goto link.sys
 input \"Enter filename w/drive: "f$
 use "b:protocol.down",255,0,f$
 goto link.sys
upload
 input \"Enter filename w/drive: "f$
 use "b:protocol.up",255,0,f$
link.sys
 link "a:system.seg"