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ODO(1)									ODO(1)

NAME
       odo - an	atomic odometer	for the	command	line

SYNOPSIS
       odo [-c | -i | -r | -s COUNT] [-p] file

DESCRIPTION
       odo  atomically updates a count in a file, which	will be	created	if not
       present.	The count is text-formatted (e.g. "00012345\n"), and  will  be
       accurately incremented or reset even when multiple processes attempt to
       change the counter at the same time. (It	uses memory mapping and	atomic
       compare-and-swap	operations to eliminate	race conditions.)

       This  could be used to track some intermittent event, like services be-
       ing restarted. Since the	counter	is just	a number in a text file,  it's
       easy ls to compose odo with other tools.

OPTIONS
       These options impact how	the counter is updated:

       -c     Print the	current	counter	value without updating.

       -i     Increment	the counter. (This is the default.)

       -r     Reset the	counter	to 0.

       -s COUNT
	      Update the counter to a specific value.

       -p     Print the	new value of the counter after updating.

EXIT STATUS
       Returns	0  if  the counter has been successfully updated. Returns 1 if
       the file	could not be read, created, or written,	or if its current con-
       tents do	not match the expected format of a counter file.

EXAMPLES
       This atomically increments a counter in /log/restarts. If  the  counter
       file does not exist, it is created as 0 and incremented to 1.

	   $ odo /log/restarts

       Same, but print the updated count:

	   $ odo -p /log/restarts

       Reset the count to 0:

	   $ ./odo -r /log/restarts

       Set the count to	a number (for testing notifications, perhaps):

	   $ ./odo -s 12345 /log/restarts

       Print the current counter value without incrementing:

	   $ ./odo -c /log/restarts

       Print usage / help:

	   $ ./odo -h

BUGS
       odo's atomicity is only as reliable as the underlying filesystem's. In-
       consistencies  may  still occur if used on a non-local filesystems such
       as nfs.

COPYRIGHT
       odo is Copyright	(C) 2014 Scott Vokes scott.vokes@atomicobject.com.

SEE ALSO
       runit(8), sqlite3(1), nfsd(8)

				 November 2014				ODO(1)

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<https://man.freebsd.org/cgi/man.cgi?query=odo&sektion=1&manpath=FreeBSD+Ports+15.0>

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