Fileechos and Magic files

Fileechos explained

The files that are received and sent along the network structure are organized in areas, called fileechos, much the same as messages are organized in echomail areas. Files are received by one system and "echoed" to other systems.

Each fileecho has a name, referred to as the "tag". Locally, a fileecho also has a large number of other options, such as the directory where files belonging to this fileecho are stored (think of messages areas for echomail areas).

Each file passed along in a fileecho is accompanied by a .TIC file. This is a small ASCII text file containing information about the associated file, such as the fileecho tag, the description, and the address where the file came from.

Following is a sample .TIC file:

Origin 2:2/2
From 1:10/1
Replaces FNEWS*.*
Desc The Fidonews: Vol#28, Issue#10 for Mar. 07, 2011
CRC 5D71E9D0
MD5 2ad9b01958c176efd35a23cfe32692e1
Created by ALLFIX, v6.00.023 Copyright (C) 2000,2011 by Bob Seaborn
Size 7705
Date 1299462301
Path 2:2/2 1299459930 Mon Mar 07 01:05:30 2011 GMT
Path 1:10/1 1299462872 Sun Mar 06 17:54:32 2011 PST
Seenby 1:140/30
Seenby 1:140/31
Seenby 1:140/32
Seenby 1:140/33
Seenby 1:140/34
Seenby 1:140/35
Seenby 1:140/36
Seenby 1:140/37
Seenby 1:140/38
Seenby 1:140/39

The first word on each line in the .TIC file is called the verb. The meaning of the verbs will be explained in the next section.

TIC file verbs

Following is a description of what each TIC verb means.

The fileecho tag.

The description for this particular fileecho. This particular verb is currently only supported by ALLFIX. When fileechos are automatically added, ALLFIX will use the description following this verb for the new fileecho.

The description of the file. Some other programs may add more than one description line to the .TIC file. ALLFIX will append any extra description lines to the first one.

The long description of the file. This particular command is currently only supported by ALLFIX and FileMgr. The long description is usually a more detailed version of the normal description and normally consists of several lines.

The network address of the system that hatched this file.

The system where this file was received from.

This field indicates who the .TIC file is for. This verb is currently only supported by ALLFIX. This verb is only included in the .TIC file when the file is being routed via another system. The presence of this verb prevents another ALLFIX from processing a .TIC file if it is destined for another system. Only if this verb is not present or if the address following it belongs to the current system, will the .TIC file be processed.

The Actual Size of the file in bytes.

The Original File Date/Time.

The 32-Bit Crc of the file. This field is used to check the integrity of the file. ALLFIX, by default, checks the Crc of all incoming files. The -NoCrc switch can be used on the commandline to force ALLFIX to not check the Crc.

The MD5SUM of the file. This field is used to check the integrity of the file. Currently only used by ALLFIX. ALLFIX, by default, checks the Crc of all incoming files. The -NoCrc switch can be used on the commandline to force ALLFIX to not check the Crc.

The file specification that this new file should replace. If enabled, ALLFIX will remove all the files that match the file specification before importing the current file. For example, if the .TIC file contains the following line:
Replaces NODEDIFF.A12
then ALLFIX will remove the file NODEDIFF.A12 from the file database and delete the actual file before importing the new file. This feature is handy for new software updates. Care should be taken since it possible to include wildcards. ALLFIX will, by default, ignore this verb, unless the option has been turned on in the fileecho configuration.

The magic name that should be updated in the mailer alias file. ALLFIX will add the current file with the magic name following this verb to the alias file to allow for file requests.

This command is used to add information about which program created this TIC file.

This extra line is added by each system that has processed this file. This line contains the unix date, a normal time and date stamp, and the address of the system that processed the file. The path lines can be used to determine how the file arrived its current destination.

This line indicates that the corresponding system has 'seen' the associated file. A .TIC file usually contains several Seenby lines. ALLFIX will not forward files to any system already in the seenby listing. ALLFIX will display a warning if a system in the systems list is already in the seenby list, making it easier to detect loops in file nets.

The password for this particular system. If the password is missing or incorrect, then ALLFIX will refuse to import the file.

TIC archive packages

Each time a file is forwarded in a fileecho, a new netmail message is created with the appropriate file attach. Large systems will quickly have problems with too many netmail messages slowing the system down.

ALLFIX is capable of compressing all the forwarded files and/or the .TIC files for a system into one archive. The advantages are that only one file is sent to a system which means that only one netmail with a file attach is required.

Because TIC archive packages can grow to be quite large, ALLFIX has the ability to set the maximum size of such a package. When a TIC archive approaches this maximum size, ALLFIX will automatically create a new archive.

The naming convention that ALLFIX uses for TIC archive packages is as follows:

The first eight digits of the filename are used to code the destination system's node number. ALLFIX can calculate a name based on the node number, but it is not possible to determine the system's node number based on the filename of the TIC archive. The extension of the TIC archive filename always begins with the letter "C" and ends with two digits. The two digits are follow up numbers. In some situations, more than one TIC archive needs to be created per system. In that case, the follow up numbers are incremented. The system has an added benefit that if two identical TIC archives arrive at a system, the mailer may automatically increment the last character of the filename, in order to prevent the original file from being over-written. In the case of a TIC archive, following the ALLFIX naming convention, the follow up number is incremented, which does not affect ALLFIX in any way. If the filename was based on the older naming convention, one would end up with file names that were no longer recognized as TIC archives.

ALLFIX will also automatically unpack the file (where xxx is a number). This file contains .TIC files and is used in the Planet Connect file distribution network.

Magic filenames explained

The magic filename system is a powerful tool that allows the user to perform specific tasks when certain files are received in certain fileechos. ALLFIX has a large number of pre-configured tasks and one of them allows external DOS utilities to be executed, making it possible to do almost anything.

One example of a possible use for magic filenames is automatically processing new node editfiles or new nodelists. The magic filename system can be configured to call up batch file that will unpack the files and call up the nodelist processor each time one of those files is received.

All the different features are explained in the section about the magic filename manager.