g++ question about what libraried

[Serge Bögeholz <serge at turing dot une dot edu dot au>]

---------- Forwarded message ----------
Date: Tue, 29 Aug 2006 14:38:28 +1000 (EST)
From: Serge Bögeholz <serge@turing.une.edu.au>
To: gnu@gnu.org
Subject: g++ question

To whom it may concern,

I'm currently using the following version of g++

g++ (GCC) 4.0.2 20051125 (Red Hat 4.0.2-8)

I was writing some code to test the  toupper(ch) library function that
is found in the cctype library.

I noticed I had not entered the line

#include <cctype>

in my C++ program,  yet my program compiled and ran correctly as though I had.

                **********************
I've included the source file as an attachment to this email, and here is the 
output of the program:

% a.out
temp = h
To upper conversion: H
                 *********************

Why did this work - all the C++ books I've read state that you need to
include the cctype library if you want to use the toupper(..) function.

Also, is there any documentation on this matter. (I've look around the GNU site 
and am at a loss as to where to look/find this type of information)

Kind regards
serge

Attachment: try.cpp
Description: Text document