To:	tony AT nt DOT tuwien DOT ac DOT at
Cc:	djgpp AT sun DOT soe DOT clarkson DOT edu
Subject:	Re: strcat() ?
Date:	Mon, 31 Oct 1994 10:15:04 +1100
From:	Peter Horan <peter AT deakin DOT edu DOT au>

> I would like to know what 
> 
> strcat(a, b);
> 
> should do when b happens to be NULL.
> I assume it should do nothing at all. Until v1.11m5 it did nothing, but
> using v1.12m2 I had to change to
> 
> if(b)
>   strcat(a,b);
> 
> to avoid concatenating some funny (nonprintable) characters to a.
> Is there any possibility to find out what libc-functions do, when an
> argument (pointer) is NULL ?

The C library string functions have an unstated precondition that string 
pointers are not NULL. It is up to the user to ensure this. strcat() will not 
test your arguments.

> 
> Tony
> 
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Peter Horan                     School of Computing and Mathematics
peter AT deakin DOT edu DOT au	   	Deakin University
                                Geelong
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