bin/142814: add beginning and end offset options to md5(1)

[Mikhail T.]

>Number:         142814
>Category:       bin
>Synopsis:       add beginning and end offset options to md5(1)
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          change-request
>Submitter-Id:   current-users
>Arrival-Date:   Thu Jan 14 04:50:03 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Mikhail T.
>Release:        FreeBSD 7.2-STABLE amd64
>Organization:
Virtual Estates, Inc. http://sybpipe.com/
>Environment:

>Description:

	When copying a huge file over a slow link, I wanted to check,
	if the already downloaded part is correct by computing the
	digests on both sides. Doing so from command line is rather
	hard right now, and requires the use of split(1) on both ends,
	which is not always feasible due to file-sizes.

	If md5(1) already had the begin and end options, I could've
	simply used them to process only part of the initial portions
	of the file on each machine.

>How-To-Repeat:

>Fix:

	The patch -- against HEAD -- can be found at

		http://aldan.algebra.com/~mi/tmp/md5-offsets.patch

	It also corrects the utility to fail with an exit-code specified
	by sysexits(3), rather than with an arbitrary 1. Also, asking for
	help (with the -h option) causes it to print the usage message
	and then exit with 0.
>Release-Note:
>Audit-Trail:
>Unformatted: