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Standard Library macros

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  Standard Library macros Raj Pashwar <raj121190@hotmail.NOSPAM.com> - 2012-07-19 17:41 +0000
    Re: Standard Library macros Ben Pfaff <blp@cs.stanford.edu> - 2012-07-19 10:46 -0700
    Re: Standard Library macros Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-07-19 21:35 +0100
    Re: Standard Library macros Nobody <nobody@nowhere.com> - 2012-07-20 07:55 +0100

#23400 — Standard Library macros

In another thread I was asking about declaring printf() without including 
<stdio.h>.

I realized that one time this will fail, is when the Platform Library 
uses a macro for printf(). Actually this is quite likely, because printf
(...) can be expanded to fprintf(stdout,...).

So I got to thinking. Is there a way to tell (by preference at compile 
time) whether a standard-library identifier, corresponds to a macro?

Cheers,
Raj

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#23401

Raj Pashwar <raj121190@hotmail.NOSPAM.com> writes:

> So I got to thinking. Is there a way to tell (by preference at compile 
> time) whether a standard-library identifier, corresponds to a macro?

#ifdef identifier?

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#23404

Raj Pashwar <raj121190@hotmail.NOSPAM.com> writes:

> In another thread I was asking about declaring printf() without including 
> <stdio.h>.
>
> I realized that one time this will fail, is when the Platform Library 
> uses a macro for printf().

An implementation is required to provide a library function even if it
is also implemented as a function-like macro.

> Actually this is quite likely, because printf
> (...) can be expanded to fprintf(stdout,...).
>
> So I got to thinking. Is there a way to tell (by preference at compile 
> time) whether a standard-library identifier, corresponds to a macro?

That's been answered: #ifdef (or #if defined).

-- 
Ben.

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#23425

On Thu, 19 Jul 2012 17:41:46 +0000, Raj Pashwar wrote:

> In another thread I was asking about declaring printf() without including 
> <stdio.h>.
> 
> I realized that one time this will fail, is when the Platform Library 
> uses a macro for printf(). Actually this is quite likely, because printf
> (...) can be expanded to fprintf(stdout,...).

Also, some versions of libintl.h have:

	#define printf libintl_printf

Simlarly for the other *printf functions.

The rationale is that libintl's printf functions support POSIX-style
positional specifiers (e.g. "%1$d"), which are particularly useful if
you're using libintl to localise format strings.

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