I’m using ccall to access a C library that has its own memory management. For the constructor and destructor calls, it expects a void**. I thought it would be most natural to create a Ptr{Cvoid} in Julia, then pass a Ref of that to the ccall. However, I get this unexpected behavior: julia> ptr = Pt…

What you want to do is impossible. If ptr is C_NULL, the only way to change that is by assigning to ptr, i.e. ptr = .... There’s absolutely no exception to this rule, you cannot implicitly modify what a variable is bound to ever. Applying to immutable types (like Ptr) this means that without reassig…

Confusion about Ptr, Ref and dereferencing

New to Julia

yuyichao December 18, 2018, 8:38pm 4

Well, you can do ptr = ptrptr[] but otherwise basically yes.

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Confusion about Ptr, Ref and dereferencing

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