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From: jafo@hpfcdc.HP.COM (Sean Reifschneider)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Determining structure field offsets
Message-ID: <11640016@hpfcdc.HP.COM>
Date: 19 Apr 89 22:09:45 GMT
References: <9270@watcgl.waterloo.edu>
Organization: HP Ft. Collins, Co.
Lines: 19

>'sizeof' operator.  Wouldn't it be correct to use something like:
>
>	offset_to_second_field = sizeof(structure.first_field)

Only if you wanted the second element of the structure.  If there
are an unknown number of elements (0..n) in the structure:

	offset_to_N_field = pointer_to_N - pointer_to_structure

or:

	struct { int foo, bar; } *baz;
	long offset;

	offset = ((long) &baz->bar) - ((long) baz);

works.

Sean