TAL Reference Manual

Standard Functions

TAL Reference Manual—526371-001

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Example of $LADR Function

In this example, $LADR returns a standard (16-bit) address from an extended (32-bit)

address:

STRING .ptr; !Declare variables

STRING .EXT array[0:99];

STRING .EXT xptr := @array[0];

@ptr := $LADR (xptr); !Return 16-bit address

! from 32-bit address

$LEN Function

The $LEN function returns the length, in bytes, of one occurrence of a variable.

variable

is the identifier of a simple variable, array element, pointer, structure, or structure

data item.

Usage Considerations

$LEN returns the number of bytes contained in a single occurrence of a simple

variable, array element, structure, structure data item, or item pointed to by a pointer.

To compute the total number of bytes in an entire array or substructure, multiply the

value returned by $LEN by the value returned by $OCCURS. To compute the total

number of bytes in an entire structure, first round up the value returned by $LEN to a

word boundary and then multiply the rounded value by the value returned by

$OCCURS.

If you apply $LEN to an unfinished structure or to a substructure in an unfinished

structure, the compiler emits warning 76 (cannot use $OFFSET or $LEN until base

structure is complete).

You can use $LEN in LITERAL expressions and global initializations, because it

always returns a constant value.

$LEN ( variable

)

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