Xref: news2.mv.net comp.os.msdos.djgpp:750
From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: calling C++ from C
Date: Fri, 02 Feb 1996 22:19:04 -0800
Organization: &tSftDotIotE
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Message-ID: <3112FE58.38BB9F9C@alcyone.com>
References: <DM4zyv DOT 5x1 AT granite DOT mv DOT net>
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Brendan Simon wrote:

> Can I call/use a C++ class from within a C program ?

No, you can't.

> If not, can I have a wrapper style function in the C++ program which will
> use the class objects ?

Yes.  The wrappers (which will be part of a C++ module, since you'll have to
have them call the C++ constructs) will need extern "C" { ... } around them.

> As I understand it, I would also need 'extern "C" {' and '}' in the C++ file.
> Is this correct ??

Correct.  You should also put the extern "C" { ... } delimiters around the
function prototypes in the header if you intend to use them from a C++ program
as well as a C program (can't hurt to do this), but remember to put the
appropriate checks to see if __cplusplus is defined; i.e., 

    #ifdef __cplusplus
    extern "C" {
    #endif

        ...

    #ifdef __cplusplus
    }
    #endif

-- 
Erik Max Francis, &tSftDotIotE. && max AT alcyone DOT darkside DOT com || max AT alcyone DOT com
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