Subject: Re: 'Safe' string copy: strlcpy() or strncpy() ?
To: Matthias Buelow <>
From: Todd Vierling <>
List: tech-userlevel
Date: 01/26/2001 16:54:38
On Fri, 26 Jan 2001, Matthias Buelow wrote:

: >Separate, though related question: should old code be converted to
: >use strlcpy() instead of strncpy()  ?
: strncpy() is portable and standardized (ANSI/ISO C), while strlcpy()
: is not (it only seems to exist in newer OpenBSD, FreeBSD and NetBSD
: versions, newer being post-OpenBSD 2.4, where it made its appearance,
: obviously).  So you chose -- more safety for inexperienced programmers
: versus portability.  I usually go for the latter.

FWIW, strlcpy() has a less well known speed advantage.  From strncpy(3):

     The strncpy() copies not more than len characters into dst, appending
     `\0' characters if src is less than len characters long,... ^^^^^^^^^
strlcpy() doesn't have this speed-impeding "feature" (dictated by ANSI in
the definition of strncpy()).

-- Todd Vierling <>  *  Wasabi NetBSD:  Run with it.
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