Is GCHandle.Alloc thread safe?

[Guest]

I use a method for threading that instantiates an object that is a wrapper to
a DLL (written in C).

The wrapper class is passed a byte array, and then does

GCHandle handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
IntPtr ptr = (IntPtr)(handle.AddrOfPinnedObject().ToInt32() +
buffer.Length-1);

It passes ptr to the DLL function FunctionX().

I've run my application in debug mode, and it errors calling FunctionX()
with more than one thread. A single thread does not cause a problem.

When I check Autos for each of the threads, one thread shows "handle" above
as being correctly allocated, and handle.Target = {System.Array}. The other
thread shows "error: cannot obtain value" for

handle.__InternalTarget
handle.IsAllocated
handle.Target

So is "handle" above thread safe? Is there a better way to do this? Thanks,

JA

 

[Guest]

By the way, "buffer" below is the byte array I'm passing to FunctionX().