Problem with Shared Parameters

[Anonymous]

What does the Meta block do in the shared parameters file, is it a versioning block for the shared parameter file or is it used by Revit for something else?

[jeremytammik]

I don't know what you mean by meta block.

[Anonymous]

Every shared parameters file starts with:

# This is a Revit shared parameter file 
# Do not edit manually 
*META	VERSION	MINVERSION
META	2	1

I was wondering what those versions are used for.

[ShawnCZirbes]

@jeremytammik 

As this question hasn't been answered since 2016, I'd like to refresh this conversation...

What is the purpose of the META VERSION and MINIVERSION fields in the 3rd and 4th rows of the shared parameter file. Is it something that Revit uses programmatically? Is it something that should be checked when reading the file to understand the potential Revit based updates to data types, or is it a benign field that we can screw with at our leisure?

I curious because, for as long as I can remember, the very first creation of the file form any Revit version always starts as META Version 2 MiniVersion 1. It doesn't appear that Revit uses it, but I don't want to attempt manipulation in case Revit does begin to use this in the future, or is using it in a way in which we are not immediately aware.

Regards,

Shawn

[RPTHOMAS108]

Have you tried changing the numbers to see what happens and why does it matter?

You want to add your own data for some reason then perhaps utilise the comment tokens #, although they may not be respected in terms of potential automatic removal.

Certain features have been added to ExternalDefinitions that didn't always exist such as HideWhenNoValue and UserModifiable. So I assume versioning was added so the inclusion/exclusion of such things could be properly interpreted. However given that the headings are all defined I wouldn't personally need such versioning to notice if a column was or wasn't there. So perhaps it was more to do with changes in integer values for categories etc.

I recall a time when the meta section didn't exist:

Extract Revit 2012 API Developer Guide

[ShawnCZirbes]

@RPTHOMAS108, I certainly have attempted changing it, and I did not see any adverse ramifications. But not immediately seeing something break, does not a safe change make... There are things we can change directly and via the API that do not immediately generate adverse effects, but also aren't necessarily the best of choices.

My intent with re-igniting an answer to the OP's questions is to get clarification on the intent. As far back as I can recall (Revit 2.8), the META version was 2 and the Miniversion was 1. I fully expected the Revit 2020+ to at least have a miniversion 2 or a full version 3 because of additions to parameter value types, but no change was noticed. As such, I'm seeking a definitive answer to weather this is a 100% unused portion of the SP files, or something that was/will be important in future versions.

Regards,

Shawn

[RPTHOMAS108]

A further thought occurred to me that occasionally category id's have been rationalised historically so it may be only to ensure that when such an id is used in a file created by an older version it is interpreted correctly in a newer version.  If there is a lack of versioning then you are set in stone in terms of making allowances for changes (so you can make no changes to format). Would assume the version changed specific to format changes rather than Revit versions. Either way I'd leave it alone as you suggest.