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FromRawPointer[p]

returns the value referred to by the pointer p for use in compiled code.

FromRawPointer[array,offset]

returns the value of a C array at an offset.

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Applications  
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FromRawPointer

FromRawPointer[p]

returns the value referred to by the pointer p for use in compiled code.

FromRawPointer[array,offset]

returns the value of a C array at an offset.

Details

  • FromRawPointer is only available in compiled code.
  • Running FromRawPointer on invalid inputs can lead to crashes.
  • FromRawPointer can work with pointers and arrays.
  • Usages of FromRawPointer have the following approximate equivalents in C:
  • FromRawPointer[p]*p
    FromRawPointer[array,offset]array[offset] or *(array+offset)

Examples

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Basic Examples  (1)

Create a pointer to an integer, then dereference it:

Wolfram Language code: cf = FunctionCompile[Function[Typed[arg, "Integer64"], With[{p = ToRawPointer[arg]}, FromRawPointer[p]] ]]
Wolfram Language code: cf[4]

Scope  (1)

Offset  (1)

FromRawPointer can extract different elements of an array:

Wolfram Language code: cf = FunctionCompile[Function[{Typed[arg, "Integer64"]}, Module[{arr}, arr = CreateTypeInstance[ "CArray"::["MachineInteger"], 2]; ToRawPointer[arr, 0, arg]; ToRawPointer[arr, 1, arg]; FromRawPointer[arr, 0] + FromRawPointer[arr, 0] ]]]
Wolfram Language code: cf[4]

Applications  (2)

Represent a library function that returns its results by modifying a pointer:

Wolfram Language code: funcDec = LibraryFunctionDeclaration["addonePointer", "compilerDemoBase", {"CInt", "RawPointer"::["CInt"]} -> "CInt"];

Compile a program that uses the function:

Wolfram Language code: cf = FunctionCompile[funcDec, Function[Typed[n, "CInt"], Module[{ptr}, ptr = Typed[ToRawPointer[], "RawPointer"::["CInt"]]; LibraryFunction["addonePointer"][n, ptr]; FromRawPointer[ptr] ]]]
Wolfram Language code: cf[12]

Represent a library function that populates a "CArray" with a sequence of square numbers:

Wolfram Language code: funcDec = LibraryFunctionDeclaration["populateArray", "compilerDemoBase", {"CArray"::["CLong"], "CLong"} -> "CInt"];

Compile a program that uses FromRawPointer to extract elements of the populated array:

Wolfram Language code: cf = FunctionCompile[funcDec, Function[Typed[n, "CLong"], Module[{arr}, arr = CreateTypeInstance["Managed"::["CArray"::["CLong"]], n]; LibraryFunction["populateArray"][arr, n]; Table[Cast[FromRawPointer[arr, i - 1], "MachineInteger"], {i, n}] ]]]
Wolfram Language code: cf[25]
Wolfram Research (2022), FromRawPointer, Wolfram Language function, https://reference.wolfram.com/language/ref/FromRawPointer.html.

Text

Wolfram Research (2022), FromRawPointer, Wolfram Language function, https://reference.wolfram.com/language/ref/FromRawPointer.html.

CMS

Wolfram Language. 2022. "FromRawPointer." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/FromRawPointer.html.

APA

Wolfram Language. (2022). FromRawPointer. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/FromRawPointer.html

BibTeX

@misc{reference.wolfram_2026_fromrawpointer, author="Wolfram Research", title="{FromRawPointer}", year="2022", howpublished="\url{https://reference.wolfram.com/language/ref/FromRawPointer.html}", note=[Accessed: 13-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_fromrawpointer, organization={Wolfram Research}, title={FromRawPointer}, year={2022}, url={https://reference.wolfram.com/language/ref/FromRawPointer.html}, note=[Accessed: 13-June-2026]}