Specifications

Chapter 14. Statement Reference
178
•
filename is the name of an FN3 function. The extension of the file names is
fixed to .FN3. (For the FN3 functions, refer to Chapter 16, "Extended Functions"
or the "BHT-BASIC Extension Library Manual.")
• functionnumber is the function number of an FN3 specified by filename.
•
data is a variable for the function number of the FN3 (that is, it is used as an
argument to the FN3 function).
• When specifying an array to
data, add a pair of parentheses containing nothing
as shown below.
Example: CALL "_xxx.FN3" 1 DATA ()
• When calling a function (specified by functionnumber) that returns a string
variable:
Reserve a storage area for a returned string variable by using a variable declara-
tion statement (
DIM, COMMON, or DEFREG). It is not necessary to assign arbi-
trary data of the string length required for a return value to the variable.
If the string length of a returned value is greater than the length reserved by a
variable declaration statement, then a run-time error will result.
(Example 1) If a return value is a fixed-length string, e.g. 8-character length:
DIM OUTPUT$[8] ' Reserve a storage area of 8 characters.
(Example 2) If a return value is a variable-length string of a maximum of N char-
acters:
DIM OUTPUT$[N] ' Reserve a storage area of a max. of N chars.
NOTE
To use FN3 functions except extended functions given in Chapter 16, you
need to download the extension programs from an extension library sold
separately.