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IntPtr and fixed

Hi All

Is IntPtr a managed or unmanaged data type in c#

Do I need to be doing
Intptr = IPtr
fixed(void * ptr = (void *)IPtr
to avoid relocation? or can I use

void *ptr = (void *)Iptr without fixed

thank yo
Nov 15 '05 #1
3 5294
Is IntPtr a managed or unmanaged data type in c#?
Managed. C# only produces managed code, you can't have any unmanaged

Do I need to be doing
Intptr = IPtr;
fixed(void * ptr = (void *)IPtr )

to avoid relocation? or can I use
void *ptr = (void *)Iptr without fixed?

Most likely no, but it depends on what the IntPtr is pointing at. I
assume you wouldn't have an IntPtr pointing to something managed
unless you had already pinned it. The first piece of code won't work


Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.
Nov 15 '05 #2
IntPtr points to a View returned by calling DLLImport MapViewOfFIle from kernel32.dll

I am compiling the code with /unsafe switch

Nov 15 '05 #3
IntPtr points to a View returned by calling DLLImport MapViewOfFIle from kernel32.dll.

Then there's no need to pin anything. The handle refers to an
unmanaged resource that's not affected by the GC anyway.


Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.
Nov 15 '05 #4

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