Short:    Alternative to SynClock, sets timezone
Uploader: Dave.Sparks@sisyphus.demon.co.uk
Type:     comm/tcp

Author:	    Dave.Sparks@sisyphus.demon.co.uk

Requires:   WB 2.04, AmiTCP
Version:    2 (no previous version on aminet)


RdateTZ is an alternative to utilities such as SynClock, which set the
local clock in accordance with the time obtained by querying the `daytime'
port (13) of a remote host.  RdateTZ improves on SynClock by:

    1	Using the `time' port (37) of the remote host, which returns
	the GMT value of the remote host's clock.  (The `daytime'
	port (13) normally returns the local time at the remote host's
	site, but could return GMT and is not required to identify the
	timezone - see RFC867.)

    2	(Optionally) ignoring a remote host whose clock is too far
	out of step with the local clock (reducing the risk of
	synchronising with a clock which is running fast or slow).

    3	Using datagrams rather than a stream, which allows several
	remote hosts to be queried simultaneously.  The first
	acceptable (see 2 above) reply is used.

    4	Using a file of timezone specifications to set the local clock
	to a specified timezone, allowing for daylight saving time if
	appropriate.  A subset of the XPG3 standard for the TZ
	environment variable is used, which allows the offsets and
	daylight saving time start and end dates of most timezones to
	be encoded.

    5	Setting a value identifying the selected timezone in the TZ
	environment variable, and recording an RFC822-compliant
	timezone identifier in the comment associated with the file
	holding this environment variable.

SetTZ provides a subset of the RdateTZ interface, which allows the local
clock to be set to a specified timezone without changing the GMT value of
the clock.  This can be called each time the machine is rebooted, or in the
early hours of every morning, to switch to or from daylight saving time on
the appropriate dates.	No attempt is made to access any external host.


============================= Archive contents =============================

Original  Packed Ratio    Date     Time    Name
-------- ------- ----- --------- --------  -------------
   10304    5516 46.4% 03-Nov-95 19:28:16  RdateTZ
   19308    7494 61.1% 04-Nov-95 08:38:10  RdateTZ.man
    3293    1564 52.5% 04-Nov-95 09:02:04  RdateTZ.readme
    1769     832 52.9% 02-Nov-95 07:31:36  TZ.dat
-------- ------- ----- --------- --------
   34674   15406 55.5% 04-Nov-95 09:36:26   4 files
