Message files

I’ve been looking at using Message files for Module Help/Syntax text and am thoroughly confused. PRM5a-36 states the Messages file format is:

token:text null-byte linefeed

Looking at a sample of Messages files from OS Modules, none have the null byte, so is PRM5a incorrect?

I also can’t figure out how to convert text to a tokenised version using the kernel dictionary. Is there a tool or SWI for this?

The null is required, but just for the Help/Syntax. You should see it in the Messages files in ResourceFS.

I have assumed the the kemal dictionary is only for the files in rom and is constructed anew with each compilation. You cannot rely on it for other Messages and it is not really necessary to save memory, except in the rom.

You should see it in the Messages files in ResourceFS

As I mentioed, I looked at a sample of Message files from Modules. For example Resources:Resources.BASIC.Messages, the null isn’t there, just the linefeed.

I have assumed the the kernel dictionary is only for the files in rom

The PRM implies the Kernel dictionary is used for all Module message files. To quote PRM5a-36:

The text is output by OS_PrettyPrint (page 1-536)– but in this case, rather than
using the kernel dictionary, it uses the dictionary in:
Resources:Resources.Kernel.Dictionary

Admittedly, it starts by saying its not using the Kernel dictionary and then quotes Kernel.Dictionary, which to any casual gamer is the Kernel dictionary!

I also can’t figure out how to convert text to a tokenised version using the kernel dictionary. Is there a tool or SWI for this?

As Steve says, the dictionary isn’t obligatory (and doesn’t make sense outside of a ROM build) – if you don’t put in an escape sequence (&1B), the text will be read normally.

Looking at a sample of Messages files from OS Modules, none have the null byte, so is PRM5a incorrect?

That’s because there’s two sorts of messages, ones a module looks up itself using MessageTrans, and ones that are looked up by *Help etc.

The syntax for a general message is

token:text linefeed

and the syntax for a help/syntax message is

token:text null-byte linefeed

I believe the reason for the difference is that a help or syntax message could have a newline in it.

You can see this in Resources:$.Resources.RAMFS.Messages: SizeErr is linefeed terminated, but HRFSRAM and SRFSRAM are zero – linefeed terminated. In the OS source, a module’s messages are generated from two files, Messages which are looked up by the module itself, and CmdHelp which has the help and syntax strings.

As Steve says, the dictionary isn’t obligatory

The only reason I’m looking at using a Messages file is to compress the Help/Syntax text.

SizeErr is linefeed terminated, but HRFSRAM and SRFSRAM are zero – linefeed terminated.

Ah..now I understand. How confusing. I’m not going to ask why Messages don’t have their own FileType, given they’re not standard text files.

The only reason I’m looking at using a Messages file is to compress the Help/Syntax text.

From what I can see there’s three options

1. If you’re building as part of an OS ROM you can make CmdHelp and Messages, then !Builder will compress it for you using Kernel.Dictionary. The dictionary is generated during the build though, so will differ between ROMs.
2. Compress the module that contains the Messages file using !ModSqz from the DDE tool collection.
3. Compress the Messages file using !Squash before embedding it in the module. MessageTrans will automatically unsquash it.

The only reason I’m looking at using a Messages file is to compress the Help/Syntax text.

It’s 2021. Memory is cheap and optimisation to save bytes is a complete waste of your valuable time. The compression in the messages file has been utterly redundant for many years, even in the ROM. Don’t bother.

However, do use Messages files, because they make internationalisation much simpler. ;-)