The  FMS/EDIT  command invokes an interactive utility that allows the
  user  to create  and  edit  a  form  on  a  VT100-compatible terminal
  screen. The Form  Editor is similar in semantics to the Form Language
  and produces an  equivalent output file.  The  command takes a single
  parameter, the form  specification. The default  input  file  type is
  FRM, and  the  default  output  file  type  is FRM.   The  /FORM_NAME
  qualifier switches the default input file  type to FLB.

  Example: FMS/EDIT FORMLIB/FORM_NAME=AFORM

     The  form  AFORM is taken from the library FORMLIB.FLB to be
     edited.

  Additional Information (explode) :

• Form specification
• Qualifiers