so far i know must be
typedef void* HTags;
Ok, thank you, changed it.
How about freepascal/lazarus can i use it...?
And if i can, can i use it in windows,linux,macosx?
The delphi class can be compiled for Win32, Win64, OSX32 (Delphi XE2), iOS and Android (XE5). Don't know about Lazarus/Free pascal, please give it a try! Maybe just a little modification is needed... what comes to my mind is don't know if TEncoding.UTF8 and TEncoding.ANSI is available in Lazarus/FP?
The latest version is here: Download Tags Library 0.1.6.4 beta.zip
Changed status to beta: all functions implemented, needs testing still.
One thing I forgot to mention is that the component is designed in the way, that it can do cross-tagging, for example load an ID3v2 tag and save it as a Flac tag. Of course not everyting is transfered but most common tags are.
And one more thing: with the .dll version it's possible to work on specific tag level (this is obvious in the Delphi version), just specify ttID3v2 for example for tag type in all functions and use SaveEx(), also now there's a GetTagData and SetTagData which can be used to work with binary data (eg. process a tag that's not implemented explicitly).