Clear

Clears or initializes some memory
Syntax
`
Declare Sub Clear cdecl ( ByRef dst As Any, ByVal value As Integer = 0, ByVal bytes As Integer )
`
Usage
`
Clear( dst, [value], bytes )
`
Parameters
`dst`
starting address of some memory
`value`
the value to set all bytes equal to
`bytes`
number of bytes to clear
Description
`Clear` sets one or more bytes in memory to a certain value (the default value is zero (`0`) if not specified). The starting address is taken from a reference to a variable or array element.
NOTE: In order to clear memory referenced by a `Pointer`, it must be dereferenced first. Otherwise, `Clear` will try to clear the bytes at the pointer variable's memory location.
Example
`
'create an array with 100 elements
Dim array(0 To 99) As Integer
'clear the contents of the array to 0, starting with the first element
Clear array(1), , 100 * SizeOf(Integer)
'allocate 20 bytes of memory
Dim As Byte Ptr p = Allocate(20)
'set each of the first ten bytes to 0
Clear *p, 0, 10
'set each of the next ten bytes to 42
Clear p[10], 42, 10
'check the values of the allocated bytes
For i As Integer = 0 To 19
Print i, p[i]
Next
'deallocate memory
Deallocate p
`
Differences from QB

- The behavior and usage is new to FreeBASIC
- The keyword `CLEAR` was used in QB to erase all variables, close all files, and optionally change the stack size. This use is not supported in FreeBASIC.

See also

- `Erase`
- `Reset`