Message-Id: <3.0.16.19971016132047.34a756c4@hem1.passagen.se>
Date: Thu, 16 Oct 1997 13:26:49 -0400
To: Jonathan Foster <jgf1 AT ukc DOT ac DOT uk>
From: Peter Palotas <blizzar AT hem1 DOT passagen DOT se>
Subject: Re: sprintf() string length?
Cc: djgpp AT delorie DOT com
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At 09.53 1997-10-16 +0100, you wrote:
>Peter Palotas wrote:
>> 
>> Is there a way to find out the length of the string that sprintf() will
>> generate, without writing it anywhere? i.e. if I want to dynamically
>> allocate the storage space for the string this would be very good (read
>> essential) to know!
>> 
>> -- Peter Palotas alias Blizzar -- blizzar AT hem1 DOT passagen DOT se --
>
>I once read a solution to this (can't remember where though!):
>
>The "fprintf" command will return the number of characters output,
>and you should fopen DOS's "NULL" file to send the output to.
>"NULL" is a "black hole" which will swallow and ignore anything you
>send to it.  Although "NULL" never appears in a directory, it
>exists everywhere.  (I think the UNIX equivalent is "/dev/nul",
>but I've never used UNIX.)

Does anyone know if this works, and how compatible it is?
Writing to a NULL pointer doesn't sound too good to me!
-- Peter Palotas alias Blizzar -- blizzar AT hem1 DOT passagen DOT se --

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