SynCro v1.41 © 1994, 1995 Simon Dainty Remote time-synchronization for AmiTCP ====================================================================== Contents: SynCro v1.41 ====================================================================== Introduction: What is...? 1.0 SynCro: 2.0 Installation ............................................... 2.1 How to...? ................................................. 2.2 Problems, problems ......................................... 2.3 Legalities... damn: 3.0 ...Forty Two: 4.0 A word in your shell-like .................................. 4.1 Past, present and future ................................... 4.2 ====================================================================== Introduction: What is...? Chapter 1.0 ====================================================================== There exists, as a part of the AmiTCP package, a mixed DOS and AREXX script named SynClock that allows you to set your local time and date to that of a remote Internet-connected system. SynCro performs the exact same function as the original SynClock, but with one distinct advantage: SynCro was written in C; SynCro is a stand-alone binary executable that can be made resident. SynCro has been fully tested with AmiTCP version 3.x beta, KickStart version 3.0 and bsdsocket.library version 2; but it should work with any version of the AmiTCP distribution and KickStart 2.0 and above (at least). I'll be happy to know of any problems people may experience with regard to running SynCro on anything other than what I was able to test it on. ====================================================================== SynCro: Chapter 2.0 ====================================================================== On startup, SynCro will first perform a check to see if AmiTCP is up and running. Next, SynCro will attempt to access the 'time' socket of the site that you have passed it as an argument at the Shell. If the attempt at accessing the port is a success then everything else is plain sailing. ---------------------------------------------------------------------- SynCro: Installation. Chapter 2.1 ---------------------------------------------------------------------- SynCro is nothing more than a standard AmigaDOS Shell command, and with that it can be placed anywhere you deem fit. Probably the best location to copy SynCro to is AmiTCP's 'bin' directory, if that is how your AmiTCP hierarchy is configured. Otherwise the C: directory is more than adequate. Placing SynCro somewhere within your path offers the obvious benefits. Alternatively, you may wish to make SynCro resident. This can be achieved by the normal method of using AmigaDOS's 'Resident' command. Making SynCro resident isn't all that big a deal though, unless you're likely to be setting your machine time on a very regular basis. Still, the option is there if you ever need it. In order to correctly calculate the current time, the GMT offset for your local site must be set via the Local preferences executable. All you need do is click on the image of your country, as displayed on the map of the world, and the local Time Zone relative to GMT will be modified to reflect your offset. Store the new local time zone by clicking on the Save gadget. If no local GMT offset is configured, SynCro will default to GMT. With respect to stack requirement, SynCro should work perfectly well with the default Shell stack size of 4096 bytes. ---------------------------------------------------------------------- SynCro: How to...? Chapter 2.2 ---------------------------------------------------------------------- SynCro requires at least one argument in order to function correctly: Either the Fully Qualified Domain Name, or the IP address, of a site. All of the valid command line arguments that SynCro will accept are listed below. SITE - This argument is the only argument required by SynCro in order for it to perform the desired task. Any valid IP address or FQDN is acceptable here. SAVE - If specified, SynCro will save the received time and date to a battery-backed clock, if such a clock exists. If SynCro is unable to access the battery-backed clock, you may be notified. IGNORE - SynCro will default to setting the local system clock to that of the remote time and date. Calling SynCro with the IGNORE switch set will result in no changes being made to the local system time at all. QUIET - Just as it says, don't bother displaying any output to the stdout. By "any," I mean that both the received date and time, as well as any errors that may occur will be suppressed. With exception to the first obligatory argument (the site), any of the three remaining arguments may be supplied or ignored at the users discretion. None of the arguments are mutually exclusive. What follows are several examples of SynCro usage: 1) Examine the current time of your local machine (read the AmiTCP documentation for information regarding 'localhost'), but do not set the system time to that of the received time. Shell> SynCro localhost IGNORE 2) Set both the system clock and the internal battery-backed clock to the time and date of the remote machine 'my.fave.remote.host'. Any output will be suppressed. Shell> SynCro my.fave.remote.host SAVE QUIET 3) Set the battery-backed clock time and date to that of the remote machine, but don't set the local system clock. I cannot think of any real reasons for wanting to do this. Shell> SynCro my.fave.remote.host SAVE IGNORE If, after receiving the remote time and date, you wish to set the local time and date, then it is simply a matter of typing: SETCLOCK LOAD at the Shell prompt. 4) Set the local system time and date to that of the remote site, but suppress all output. Nothing will be written to the battery- backed clock. Shell> SynCro 255.255.255.255 QUIET ---------------------------------------------------------------------- SynCro: Problems, problems. Chapter 2.3 ---------------------------------------------------------------------- If, for some reason, SynCro is unable to perform its duty - if the remote host can't be found for example, a specific return code shall be met. The value of the return code relates directly to a specific error within SynCro, these errors are listed below: 21 - Incorrect command line arguments were passed. 22 - SynCro couldn't open the bsdsocket.library. 23 - SynCro failed to connect to the given remote host. 24 - SynCro was unable to connect to the 'time' socket of the remote host. 25 - For some reason, the battery-backed clock could not be found. The returning of an error-specific return code was a new feature of SynCro, for version 1.1. ====================================================================== Legalities... damn: Chapter 3.0 ====================================================================== You use SynCro completely at your *own* risk, no warranty is either expressed or implied. I cannot (and will not) be held responsible for any damages caused by SynCro, no matter what the circumstance. Either use this program or ignore it, but don't blame me for *any* unwanted results. I've probably spent more time testing SynCro than actually coding it and not once has it misbehaved. Hopefully you too should experience a care-free service life. Although SynCro is freely distributable, it still remains copyright 1994-5 Simon P. Dainty. SynCro is definitely not Public Domain, it is freely distributable FreeWare - there is a difference. Anyone wishing to obtain a copy has the right to a copy, for little or no charge. Whilst the continued distribution of SynCro is the author's goal, he hopes that you will conform to the following agreement: 1) No files are added to, or removed from, the archive with respect to the original distribution, and no files are modified relative to their original state without the author's permission. 2) No charge, other than the cost of media duplication, may be asked for this package unless the situation of that charge falls within item three (below). 3) If this package is to be included as a part of a commercial or ShareWare (or variant) distribution, or magazine coverdisk, the author would appreciate some form of prior notification. Aminet CD-ROM, or any "Public Domain" CD-ROM distribution is exempt from the above requirement. If you are a non-conformist, at least make the effort to appreciate what I've written above. =o) Above all though, have fun. ====================================================================== ...Forty Two: Chapter 4.0 ====================================================================== SynCro was written in C, with the aid of Matt Dillon's DICE C package (version 2.07.57R) and was tested on a 3.0-based AGA Amiga, running AmiTCP v3.xbeta and bsdsocket.library version 2. Even though SynCro is freely distributable, I'd like you to think of it as "World-a-Ware". If you find SynCro to be useful, or you use SynCro for any period of time, please do a little something to help the environment of OUR home. We are all ultimately responsible for the world that we live in, and we are equally responsible for those we share it with. We only have the one copy of Earth, and without a back-up... ---------------------------------------------------------------------- ...Forty Two: A word in your shell-like. Chapter 4.1 ---------------------------------------------------------------------- With respect to bug fixes, bug reports, general updates (if any) and pure talkability, I can be contacted at any of the addresses listed below. You will also find me lurking in most all of the Amiga related Usenet groups, specifically the comp.sys.amiga.* groups as well as a good few Amiga specific FidoNet and AmigaNet echos. Internet mailbox: syncro@ancient.demon.co.uk (Simon Dainty) Or, izzy@ancient.demon.co.uk (Simon Dainty) FidoNet and AmigaNet, via Dox's Amiga BBS (+44 01943 850340): 2:250/320.3 (Simon Dainty) 39:138/14.3 " " Snail mail: 25, Victor Road, Heaton, Bradford, West Yorkshire, England, BD9 4QN. Electronic mail is my most preferred form of communication. SYL, Si. "Breakin' outta school an' we were kickin' hard. A lotta good dreams an' a lotta false starts; We swore we wouldn't get old before our time..." - Little Angels. ---------------------------------------------------------------------- ...Forty Two: Past, present and future. Chapter 4.2 ---------------------------------------------------------------------- 29-Nov-94: v1.0 - Initial release with no know bugs. Limited distribution. 02-Dec-94: v1.1 - Optimized executable compilation by utilizing inline library calls. Shaved off around 200 bytes from the binary. - SynCro will return a specific code in the event of an error. Refer to chapter 2.3 for more information. 02-Jan-95: v1.2 - Optimized executable size. Now down to 4.8K. - Modified the ordering of the error-specific return codes into something a little more logical. Please refer to chapter 2.3 with respect to those changes. - Fixed a bug where SynCro would complain about an invalid FQDN argument, when the argument was indeed valid. 28-Jan-95: v1.3 - Optimized executable size. Now down to 3.5K. - SynCro now goes directly through the "bsdsocket.library", as opposed to earlier versions that used the TCP: device. This affords the user several benefits: * Not restricted to only giving an FQDN as the reference to a remote site; SynCro will also accept an IP address. * No need to mount the TCP: device if SynCro was the only program that needed it. * A CONTROL-C from the Shell that SynCro was started from will now stop it dead in its tracks. - Once more, several modifications have been made to the error- specific return codes. Please refer to chapter 2.3 for more information. 04-Feb-95: v1.4 - Limited tester release. - Problems arose when SynCro was used with the Multilink AmiTCP and RS225 emulator (in beta). Thanks to Osma Ahvenlampi for pointing the deficiency out. - If SynCro was unable to resolve the remote host, AmiTCP would not shutdown correctly. This was a problem with version 1.3 of SynCro not closing the bsdsocket.library when it should have done. Any other time and it would have worked fine. My fault entirely - it is now fixed. - Minor changes to the error-specific return codes. Again. 09-Feb-95: v1.41 - Modified the way the remote time is processed. Instead of relying on the location-specific time string as received via the 'daytime' port, SynCro now goes through the 'time' port, and calculates the current time by processing the number of seconds since midnight of January the 1st 1900. - Because of the above changes, SynCro now requires the local system's GMT offset to be set within the Locale preferences.