From: bill@bilver.uucp (Bill Vermillion)
Subject: Re: Reliable backup software
Organization: W. J. Vermillion - Winter Park, FL
Date: Sun, 22 Nov 1992 03:43:52 GMT

In article <2978@mitisft.Convergent.COM> dold@mitisft.Convergent.COM (Clarence Dold) writes:
>From article <1992Nov13.200327.6049@panix.com>, by dans@panix.com (Dan Simoes):

>> 	Recently there have been a few articles in the *ix magazines about
>> backup software.  Basically they focused on the fact that you never really 
>> know your data is safe unless you do a restore of that data.

>There was a comment about LoneTar being junk.  There are three very closely
>related companies, LoneStar, Cactus International, and UniTrends.  They
>offer almost identical products except that UniTrends offers CTar, rather
>than LoneTar.  CTar offers a "ctar -t" option, just like tar -t, and ctar
>-T, where the UpperCase causes a true compare.  After a full backup, the -T
>option tells me that /etc/utmp is a different size, and that /etc/wtmp
>failed to compare (or vice versa).

Well there was a program that floated across the net a couple of years
ago.  I use it for checking files I archive permanently to floppies,
and it picks up errors now and then.   I use ctar for others and
assumed it's verify really works.

I don't have much info on this as it appears I stripped the headers
from the file.

This shows where it came from.
/*+-------------------------------------------------------------------------
	cktar.c - read a tar tape and compare against file system
	wht@n4hgf.Mt-Park.GA.US
--------------------------------------------------------------------------*/
/*+:EDITS:*/
/*:11-08-1990-16:34-wht-creation */


And here is the 'doc' section.

char *usage_text[] =
{
"usage: cktar [-t] [-v] [-A] [-U] [-G] [-M] [-f tar_input_file] [--]",
"This program reads a tar input file and compares each",
"file on the volume with a matching file on disk.",
"",
"If a file on the tar file has the same length as a file on the",
"disk, the files are compared byte for byte and the byte position",
"of the first nonmatching byte is printed.",
"",
"If a file on the tar file has a different length from a file on",
"the disk, this fact is noted.",
"",
"If the -U switch is present, UIDs must match.  If the -G switch is",
"present, gids must match.  If the -M switch is present, times of last",
"modification must match.",
"",
"With -t or -v switch, no output is produced for matching files.",
"With -t, a title is printed for each file regardless of match.",
"With -v, this output is expanded to show all attributes of the file",
"on the tar file as well as the match status.",
"",
"If you wish to have cktar read from stdin and do not wish to use",
"any of the available switches, use the '--' switch.",
"",
"The -A switch acts like the tar A key, causing a leading '/' in",
"a tar input filename to be elided.",
"",
"Exceptions are reported by codes appearing after filenames:",
"   A - stat access denied",
"   N - non-existent file",
"   U - uid difference",
"   G - gid difference",
"   T - time of last modification difference",
"   S - size difference",
"   C - comparison failed at position shown by decimal value after C",
"The 'S' and 'C' codes will never appear together, 'A' and 'N' will",
"never appear together or with any other codes, but any other mixture",
"of codes is possible.  Only the C code has a decimal file position",
"appended.",
"",
(char *)0
};


The source is about 14k.  There is no copyright in the copy I have.

If someone knows who wht@n4hgf is, or if he's reading this, I'd just as
soon have the author repost it.  If not, I guess I could put it here
(or somewhere appropriate).


-- 
Bill Vermillion - bill@bilver.oau.org  bill.vermillion@oau.org
                - bill@bilver.uucp 
                - ..!{peora|tous|tarpit}!bilver!bill