std::unique_ptr and pointer to pointer

Question

I want to use std::unique_ptr in combination with FreeImage\'s FITAG. The code in plain C would be:

... load image;

FITAG* tag = NULL;
FreeImag         


        

Answer 1

Reverse the order of operations; first acquire the resource and then construct the unique_ptr.

FITAG *p = NULL;
FreeImage_GetMetadata(FIMD_EXIF_EXIF, bitmap, "Property", &p);
std::unique_ptr tag(p, &FreeImage_DeleteTag);