Pointer Ptr

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Pointer | Ptr

A variable declaration type modifier

Syntax

... As DataType {Pointer | Ptr}

Description

Declares a pointer variable.
The variable type can be a predefined type or a user-defined type.

Operator @ (Address Of) operator or VarPtr are used to take the address of a variable. The Operator * (Value Of) operator is used to dereference the pointer, that is, access the actual value stored in the memory location the pointer is pointing at.

Remarks

Dialect Differences

• Not available in the -lang qb dialect unless referenced with the alias __Pointer or __Ptr.

Differences from QB

• New to FreeBASIC

See also

• Allocate

Examples

' Create the pointer.

Dim p As Integer Ptr

' Create an integer value that we will point to using pointer "p"

Dim num As Integer = 98845

' Point p towards the memory address that variable "num" occupies.

p = @num

' Print the value stored in memory pointed to by pointer "p"

Print "Pointer 'p' ="; *p

Print

' Print the actual location in memory that pointer "p" points at.

Print "Pointer 'p' points to memory location:"

Print p

Dim p As ZString Pointer

Dim text As String

text = "Hello World!"

p = StrPtr(text) + 6

Print text

Print *p

'' Output:

'' Hello World!

'' World!

Type mytype

    a As Integer = 12345

End Type

Dim As mytype mt

Dim As mytype Ptr pmt

pmt = @mt

Print (*pmt).a  '' or Print pmt->a

'' Output:

'' 12345

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Category: Standard Data Types
Kind: keyword

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