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The SysOP's Companion
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The SysOP's Companion (Tropical Publishing) (1993).ISO
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readme.199
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1992-08-30
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5KB
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112 lines
;S |
;S |
;S | THIS NODEDIFF MUST ONLY BE MERGED WITH A
;S | NODELIST.192 THAT HAS A VALID CRC VALUE OF
;S | 12600 AT THE RIGHT END OF THE FIRST LINE AND
;S | IS NOT LESS THAN 1,443,264 BYTES LONG.
;S |
;S |
;S | I F Y O U R N O D E L I S T . 1 9 9 D O E S N O T H A V E
;S |
;S | C R C V A L U E 1 2 6 0 0
;S |
;S | D O N O T P R O C E S S T H I S N O D E D I F F
;S |
;S |
;S | IF YOUR SOFTWARE HAD TROUBLE MERGING NODEDIFF.192
;S | WITH NODELIST.195 YOU WILL HAVE TROUBLE WITH THIS
;S | NODEDIFF. IN THAT CASE THE ONLY 100% SAFE SOLUTION
;S | IS TO OBTAIN FULL NODELIST.?99 FROM YOUR NETWORK OR
;S | REGION COORDINATOR AND RETURN TO NORMAL PROCESSING
;S | WHEN NODEDIFF.206 IS DISTRIBUTED.
;S |
;S |
;S | D O N O T T A M P E R W I T H T H I S N O D E D I F F T O
;S |
;S | M A K E I T W O R K . I F I T F A I L S T O M E R G E
;S |
;S | P L E A S E D O N O T T A K E C H A N C E S .
;S |
;S |
;S | A file called CRCNODE.ARC has been hatched into the COORDUTL
;S | file echo. The program can be executed wherever your nodelist
;S | is located to help with validation. If the program reports
;S | an error you should get a correct nodelist from your NC or RC.
;S |
;S |
;S | Several days ago I announced to the Zone 1 Region Coordinators
;S | that I planned to release NO nodediff.199 and release only a
;S | full nodelist.199 in its place. A majority of the Region
;S | Coordinators questioned that plan. They offered evidence that
;S | many, many of Zone 1's nets had already spent the weekend and
;S | part of this week preparing for distribution of nodediff.199.
;S | They indicated that although from my vantage point the no
;S | nodediff scenario was the "safe and easy" way to proceed they
;S | and the Network Coordinators all over Zone 1 could handle the
;S | situation without forcing everyone in the zone to accept a full
;S | nodelist. The RCs feel that this is a more cost effective
;S | solution as well as one that allows local solutions rather than
;S | ones dictated from far away. Their arguments were convincing and
;S | accepted as offered.
;S |
;S | If you don't fully follow what happened last week please read
;S | on. If you still have concerns about the nodelist on your system
;S | you should get a fresh one from your NC or RC or ZC in that
;S | order to share the load.
;S |
;S |
;S | Last week's Nodediff.192 created a little stir around zone 1. As
;S | the condensed story goes, a carriage return (CR or hex 0d) and a
;S | semicolon (;) sneaked into one network's segment as excess data
;S | and escaped detection by the MakeNL software that merges
;S | nodelist components on both the RC and ZC machines. Some ask
;S | "Isn't CR always the end of a line and not data?" Well, not if
;S | your software uses the C language text read routines to process
;S | network and region segments. Those routines require both CR and
;S | LF (linefeed) to appear together before they pay attention. But
;S | if your software uses the Pascal language text read routines CR
;S | is indeed seen as an end of line indicator the same as CR and LF
;S | together. That's our problem. Different interpretation of the
;S | same data.
;S |
;S | We have one program building the nodediff using one rule and
;S | many others processing it using another rule. As always, two
;S | opinions have been shared. One says MakeNL is broken. The other
;S | says certain nodelist compilers are broken. I think we've just
;S | found an exception that none of the programs were looking for.
;S |
;S | FidoNet nodediffs are based on a strict count of the number of
;S | lines in the nodediff itself and in the nodelist. If a line is
;S | added or deleted from either file, we have trouble. That's what
;S | the Pascal based programs reported last week while the C
;S | programs chugged along quietly.
;S |
;S | The Pascal based programs processed an A3 (Add the next 3 lines)
;S | command and added the next 3 lines they read. The line
;S | immediately after the 3 added lines was supposed to be another
;S | command -- Add, or Copy, or Delete. Remember that sneaky CR? Well,
;S | it joined forces with the Pascal read routines to make 4 lines out
;S | of 3. In this case the original third line following A3 became
;S | the fourth so the programs expected a command. It found
;S | Host,3808,... instead. That's a fatal error for any
;S | nodediff/nodelist merge program.
;S |
;S | Many of us saw that fatal error. Reactions varied from curiosity
;S | to anger. But thanks to the efforts of many folks the impact was
;S | reduced to a minor annoyance in all but a few remote areas.
;S |
;S | This week the ZC's machine is running nodelist checking software
;S | that hopes to either prevent occurrence of a similar event or
;S | not publish the nodediff if it does happen.
;S |
;S | We now know about a situation where data can sneak in and gum up
;S | the works. I suspect a few nodelist processing software authors
;S | are taking another look at FTS-0005 (our nodelist contents
;S | standard document) and shoring up their software to allow for
;S | similar situations in the future.
;S |
;S |
;S | Thanks for all your efforts.
;S | George Peace
;S |