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Re: Incompatibility between ncurses and libc6?



On Sat, 31 Oct 1998 22:34:28 +0100, Martin Schulze <joey@finlandia.Infodrom.North.DE> said:
> Brandon Mitchell wrote:
>>>
>>>      75 #if HAVE_TERMIOS_H && HAVE_TCGETATTR
[...]
>
> #if is correct, however if you use if you also have to use "defined()"

That isn't so.  The preprocessor treats undefined tokens as 0 in
expressions.

    $ cat t.c
    #define YES 1
    #if UNDEF && YES
	one
    #endif
    #if UNDEF || YES
	two
    #endif
    $ gcc -E t.c
    # 1 "t.c"





	two

    $ _

-- 
Roderick Schertler
roderick@argon.org


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