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From: gwyn@smoke.brl.mil (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: Simple ptr passing question
Message-ID: <16159@smoke.brl.mil>
Date: 15 May 91 21:35:01 GMT
References: <24268@unix.SRI.COM> <13012@uhccux.uhcc.Hawaii.Edu>
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 15

In article <13012@uhccux.uhcc.Hawaii.Edu> morrison@uhhacb.tmc.edu (Jay Morrison) writes:
>The problem is that in C you always pass by reference, ...

No, it's always pass by value, which agrees with the further description
you gave.

>Another common problem you may encounter is a returning a FILE*
>structure from a routine which opens a file.  In this situation you must
>also use pointers to pointers.  This even had my professor confused as
>to what was happening!! (temporarily).

The standard practice for such a function is to make the FILE* its
return value, e.g.
	extern FILE *my_open( const char *name );
with a null pointer being returned when the function fails.