Directives
DEF ....  
  The DEF directive has a variety of formats that allow for the defintion of objects, functions, and other system values.

Please select the format you are interested in
   
Formats DEF CLASS class$... Use the DEF CLASS directive in Object Oriented Programming (OOP) to declare the start of an object definition. It defines the name of the object and it can be used to override object creation and deletion logic
  DEF OBJECT... Use the DEF OBJECT directive is used to create a new instance of a specified COM object.
  DEF FNvar$(arglist) ... Use the DEF FN directive to define single- or multi-line functions.
  DEF [ CVS | DTE | LCS | UCS ] ( new_table$ ) Use these DEF directives to define new system tables for Accent Conversion, Date,
  DEF [ CTL | ERR | LFO | LFA ] = numval Use these DEF directives to set the values for various system variables. (implemented in VERSION 7)
  DEF MSG ( msg_text$ ) Use the DEF MSG directive allows you to change system messages on-the-fly.
  DEF GID = groupID
DEF UID = UserID
Use the DEF GID= and DEF UID = directives to override the effective UNIX/Linux user or group ID of a session, if OS security allows it.
  DEF ARG( nn ) = string$ Use the DEF ARG to change the value associated with a ARG for the duration of the session.