From owner-freebsd-questions  Wed Jan 31 19:45:45 2001
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From: Mike Meyer <mwm@mired.org>
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Date: Wed, 31 Jan 2001 21:45:27 -0600 (CST)
To: lucas@slb.to
Cc: questions@freebsd.org
Subject: Re: Printf question
In-Reply-To: <20010131213515.A12876@billygoat.slb.to>
References: <109394@toto.iv>
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	<20010131213515.A12876@billygoat.slb.to>
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Lucas Bergman <lucas@slb.to> types:
> > > What you probably want is the `%llu' specifier instead of `%ld'.
> > > Note that `long long' is a _very_ recent addition to the C
> > > standard, so proceed with caution if you want your program to be
> > > portable.
> > 
> > The man page doesn't mention ll as a modifier, but talks about q. I
> > get the results he wants with %qd, %qu, or %llu - but not %lld.
> > -Wall doesn't complain about either one (on -current, anyway).
> 
> Hrmm?
> 
>   roostor % echo 2 ^ 35 | bc
>   34359738368
>   roostor % cat foo.c
>   #include <stdio.h>
> 
>   int
>   main(void)
>   {
>     long long x = 1LL << 35;
>     printf("%lld\n", x);
>     return 0;
>   }
>   roostor % gcc -Wall foo.c
>   roostor % ./a.out
>   34359738368

If you look at the original code, he was using an unsigned long
long. %lld in that case gave different results from %qd, %qu, and
%llu.

Possibly it's a bug.

	<mike
--
Mike Meyer <mwm@mired.org>			http://www.mired.org/home/mwm/
Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information.


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