Core Function BinaryMid

BinaryMid( <binary-array>, <start>, <length> )

Description

Create a binary variable by extracting a number of bytes from another binary variable.

Parameters

binary-array

The binary variable to use.

start

Position to start from.

If the start is a negative value the position will work backwards from the length of the binary.

length

Optional; How many bytes to copy.

Default is all remaining bytes;

If length is given and is negative, then that many bytes will be omitted from the end of binary (after the start position has been calculated when a start is negative).

If start denotes the position of this truncation or beyond, empty binary variable will be returned.

Return Value

Success: Returns a new binary variable.

Failure: Returns empty binary variable.

Remarks

This does not modify the original.

Example

Copy from "brown" to end of the data:

$binary = Pack("A*", "The quick brown FoX");
$binary2 = BinaryMid($binary, 10);
println("b1: " . Unpack("A*", $binary, 3));
println("b2: " . Unpack("A*", $binary2, 3));

Copy just the "FoX" part example:

$binary = Pack("A*", "The quick brown FoX");
$binary2 = BinaryMid($binary, 16, 3);
println("b1: " . Unpack("A*", $binary, 3));
println("b2: " . Unpack("A*", $binary2, 3));