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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 accu-
     rately incremented or reset even when multiple processes attempt to  change
     the  counter  at  the  same  time.  (It uses memory mapping and atomic com-
     pare-and-swap operations to eliminate race conditions.)

     This could be used to track some intermittent event,  like  services  being
     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 contents 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. Incon-
     sistencies 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+15.1.quarterly>

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