Function Subroutines - AMX NETLINX PROGRAMMING LANGUAGE Manual

For special cases where multiple copies of a system call are needed, an instance number can be specified
in the call. The compiler will compile a separate copy of the subroutine for each system call instance
number. For example, the following commands force the compiler to include two separate copies of
:
COSX
SYSTEM_CALL[1] 'COSX' (45)
SYSTEM_CALL[2] 'COSX' (60)
This technique could be useful in cases where a system call contains a wait instruction that conflicts
when multiple calls to the same subroutine were made during a single wait period.

Function Subroutines

A function is similar to a
expression. Instead of requiring a string literal for its name, it requires a name that follows the rules for
naming constants and variables. This eliminates the need for using the
subroutine.
returned using the
The return type may only be one of the 8 intrinsic types. Strings, arrays, structures,
classes and other user-defined types may not be returned.
Syntax:
DEFINE_FUNCTION [<return type>] FnName[(Param1,Param2,...)]
{
}
You cannot declare and initialize variables in the same line.
You must group the declarations first, followed by the initialization.
Example:
DEFINE_FUNCTION INTEGER myFunction (INTEGER Var0)
{
}
When it is a NetLinx function, a syntax where there appears a ([ ]), the ( ) are NOT
OPTIONAL but the [ ] are optional.
The DEFINE_FUNCTION subroutine can be called as a single programming statement. For example,
the following syntax:
NetLinx Programming Language Reference Guide
DEFINE_CALL
subroutines also differ from
DEFINE_FUNCTION
statement (see below).
RETURN
(* statements *)
INTEGER nBytes
STACK_VAR RESULT
nBytes = 0
RETURN = Var0 + nBytes
RETURN RESULT
, but is intended for use either standalone or in-line as an
DEFINE_CALL
Language Elements
keyword to invoke the
CALL
by allowing values to be
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