From: wkt@tuhs.org (Warren Toomey)
Subject: [TUHS] History of strncpy
Date: Wed, 23 Jan 2013 14:41:08 +1000 [thread overview]
Message-ID: <20130123044108.GA2871@neddie.local.net> (raw)
In-Reply-To: <CAGg_6+MMAB9pqrMkiD7kd8gGyRYdSDeV9AZ7zaAOC9etO=GP1Q@mail.gmail.com>
On Tue, Jan 22, 2013 at 10:03:54PM -0600, Nevin Liber wrote:
> The original reason for strncpy() was when directory names were limited to
> 14 chars. The other two bytes contained the inode number. For that
> particular case, strncpy() worked quite well.
>
> Is that really the reason it came into being?
strncpy() was introduced in 7th Edition Unix. From a quick perusal through
the V7 source code, these files used strncpy():
usr/src/cmd/ranlib.c strncpy(firstname, arp.ar_name, 14);
usr/src/cmd/login.c #define SCPYN(a, b) strncpy(a, b, sizeof(a))
usr/src/cmd/expr.y strncpy(Mstring[0], p, num);
usr/src/cmd/atrun.c strncpy(file, dirent.d_name, DIRSIZ);
usr/src/cmd/ed.c strncpy(buf, keyp, 8);
usr/src/cmd/mkdir.c strncpy(pname, d, slash);
usr/src/cmd/xsend/lib.c strncpy(buf, s, 10);
usr/src/cmd/crypt.c strncpy(buf, pw, 8);
Only two of these (ranlib.c and atrun.c) appear to be specifically related
to the 14-byte filename limit in V7. So I'd say that strncpy() wasn't
introduced solely to deal with 14-byte filenames.
Cheers,
Warren
next prev parent reply other threads:[~2013-01-23 4:41 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-23 4:03 Nevin Liber
2013-01-23 4:41 ` Warren Toomey [this message]
2013-01-23 4:58 ` Warner Losh
2013-01-23 14:16 ` Clem Cole
2013-01-23 15:01 ` Ronald Natalie
2013-01-23 15:24 ` Armando Stettner
2013-01-23 17:49 ` scj
2013-01-23 18:19 ` Ronald Natalie
2013-01-23 19:33 ` Ronald Natalie
2013-01-23 19:59 ` Clem Cole
2013-01-23 22:43 ` Mary Ann Horton
2013-01-24 0:01 ` Clem Cole
2013-01-24 0:37 ` Jonathan Gevaryahu
2013-01-23 17:56 Michael Spacefalcon
2013-01-23 21:08 ` Larry McVoy
2013-01-23 21:39 ` Ronald Natalie
2013-01-23 21:46 ` John Cowan
2013-01-24 6:02 ` Larry McVoy
2013-01-24 6:34 ` Steve Nickolas
2013-01-24 14:42 ` Ronald Natalie
2013-01-24 14:52 ` Warner Losh
2013-01-24 16:01 ` Ronald Natalie
2013-01-24 18:31 ` Tom Ivar Helbekkmo
2013-01-25 2:06 ` Warner Losh
2013-01-24 16:21 ` Clem Cole
2013-02-01 0:28 ` Larry McVoy
2013-01-31 23:52 ` Random832
2013-02-01 0:06 ` Warner Losh
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