chdman addmeta and delmeta do not work

[johnsanc314]

MAME version

0.262

System information

Windows 11

INI configuration details

No response

Emulated system/software

No response

Incorrect behaviour

chdman's addmeta and delmeta actions do not work. A "file not writeable" error is always returned.

Expected behaviour

chdman's addmeta and delmeta actions should add and delete metadata like it did with 0.146 and earlier.

Steps to reproduce

1. Try to use addmeta with any chd. It fails.
2. Try to use delmeta with any chd. It fails.

Additional details

As far as I can tell, this bug has been present for over 11 years dating back to 0.147.

Past reports:
mameworld.info bug report
mametesters ID:5079

[Osso13]

You need to create and use an uncompressed chd to use thosee commands. Then you can compress it.

[johnsanc314]

Thanks for the tip. There is no documentation I could find that compression = none is a requirement. The error message and/or command line help should mention this.

Also, why is it a requirement to have no compression for this to work? That doesn't make any sense to me considering it seems to work the same way it did with version 0.146 which didn't have this restriction. The extra meta info is tacked on the end of the CHD just like it was before with compressed CHDs.

Also, is there a way to add metadata during initial chd creation? Seems a little silly to have to create an uncompressed chd first just to add metadata then compress with the copy command