As I have not found a quick and easy guide on how to use mp3fs in OSX I'll write this in english.
The concept of mp3fs is a FUSE filesystem which converts FLACs to mp3s on the fly (CBR only as of now) via lame. Thus you can have the original FLACs stored, and expose a folder structure of converted mp3s to whatever you want. In my case iTunes.
This is all pretty easy under Linux, but in OSX there are a few hurdles along the way. First one is that the current OSX patch for mp3fs is only compatible with the Macports version of MacFUSE (currently 1.7_1). So any currently installed MacFUSE package (via DMG or otherwise) has to be removed.
Once this is done installing mp3fs and MacFUSE is as easy as installing the mp3fs port. Here is a step-by-step working guide (tested with OSX Leopard 10.5.7).
1. Install Macports (http://www.macports.org/install.php).
2. Open your favourite terminal.
3. “sudo port install mp3fs”
4. Make yourself a nice cup of your favourite hot beverage.
5. Create a mountpoint : “mkdir mp3fs”
6. Mount the mp3fs : “sudo mp3fs /Path/To/Your/FLAC/Dir,BITRATE /Path/To/Your/Mountpoint -o allow_other,ro”
Example : “sudo mp3fs /Users/denis/Music/CDRips,256 /mnt/mp3fs -o allow_other,ro”
7. You now have an mp3fs filesystem at /mnt/mp3fs 🙂
Running “mp3fs” with no options will show usage (no manpage yet), and running “mp3fs /Dir1,256 /Mountpoint -h” will show you FUSE mountoptions, one of these is -d for debug which could come in handy.
Thanks to the coders of this nifty little FUSE fs, and to the guys patching it for OSX. Any chance we could have a cleaner patch that would also work with newer MacFUSE versions?