Can gnu global restrict references to variable "modification" or "read" operations ?

Hello Gnu Global,

I was wondering if it would be hard to modify gtags so that it would
remember the references (for variables) as being "modified/written"  or
being "read". Then, global can, possibly with a flag show us just the
references that are modifying  a variable or just reading the variable or
either/other (such as the symbol's  presence in declaration of a function,
or definition in a class/struct.)


I tried to look at gtags.c, but I could not frankly make enough sense to
know just how to go about this. It seems schema of GRTAGS  db would have to
change a bit to add at least a column for "type_of_symbol_reference"?

Gautam