$ sort /? |head
SORT [/R] [/+n] [/M kilobytes] [/L locale] [/REC recordbytes]
  [[drive1:][path1]filename1] [/T [drive2:][path2]]
  [/O [drive3:][path3]filename3]
  /+n                         Specifies the character number, n, to
                              begin each comparison.  /+3 indicates that
                              each comparison should begin at the 3rd
                              character in each line.  Lines with fewer
                              than n characters collate before other lines.
                              By default comparisons start at the first
                              character in each line.

$ gsort /?
gsort: open failed: /?: Invalid argument