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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Parsing struct memory?
Date: Thu, 16 Mar 2017 19:14:59 -0700
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Thiago Adams <thiago.adams@gmail.com> writes:
> Having some struct;
>
> struct {
>   char c;
>   void* p;
>   double d; 
> };
>
> Is it possible to parse it just knowing each type?
> Something similar of var_arg but for structs.
>
> char c = arg(pointer, char);
> void* p = arg(pointer, void*);
> double d = arg(pointer, double);

Not easily or portably.

Once upon a time, I worked on a project that parsed C declarations to
generate C code that would print out the sizes and offsets of all the
members of all the structures in a set of C headers.  The intent was to
use that information to generate code that could access struct members
by name at run time from raw data transmitted to a system with a
possibly different architecture.  (I don't have any of the source code.)

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"