Re: m4 bug in format.c (m4 v1.4)

[Gary V . Vaughan]

On Friday 06 April 2001  8:06 am, address@hidden wrote:
> Version:
> m4 version 1.4, all operating systems
>
> Problem description:
>
> The format macro returns a wrong output if you specif an integer number 
that terminates with a 0, example try to output the number 10 using:
>   > format(%f, 10)
>
>   1000000

Agreed.  Thanks for the patch -- applied to CVS HEAD.

> One thing I don't understand is why the format command has an own
> implementation, wouldn't it be better to simply use vsprintf() instead ? My
> guess is that vsprintf() is not implemented or not consistent on all
> operating systems ?

There is no portable way to build a va_list in memory to pass to vsprintf -- 
building an array of void* works with some compilers, provided the memory 
alignment expected on the call stack matches the alignment of the array on 
the heap.  Worse, some compilers implement va_list's without using void* 
arrays at all.

Cheers,
        Gary. 
-- 
  ___              _   ___   __              _         mailto: address@hidden
 / __|__ _ _ ___ _| | / / | / /_ _ _  _ __ _| |_  __ _ ___       address@hidden
| (_ / _` | '_|// / |/ /| |/ / _` | || / _` | ' \/ _` | _ \
 \___\__,_|_|\_, /|___(_)___/\__,_|\_,_\__, |_||_\__,_|//_/
home page:  /___/                      /___/                  gpg public key:
http://www.oranda.demon.co.uk           http://www.oranda.demon.co.uk/key.asc