Hi,

I need similar functionality like mp3 players have (e.g rhythmbox, banshee, clementine). I have some experience with databases (I worked in company which make ERP systems), but don't know how to connect it with file handling.

My general questions are:
1. I have big collection of music. First indexing in random music player take some time, but refreshing collection take only a second. How they do this? They are saving folders last change date?
2. Some players have option which detect when collection is changed and automatically can refresh it (even if player is actually running). How it works? Some hook for folders?

Any tips, algorythms are welcome. Oh, I need this for linux and windows targets

Regards

When indexing the first time they must see if a file is known or not. This takes time. During refresh they know the names, they just need to update.

2. Some players have option which detect when collection is changed and automatically can refresh it (even if player is actually running). How it works? Some hook for folders?

The inotify calls are available on Linux. It tells you when a file/folder changes:

function inotify_init: cint;
function inotify_init1(flags:cint):cint;
function inotify_add_watch(fd:cint; name:Pchar; mask:cuint32):cint;

These calls are available in the linux unit. I have an article that describes how it works, if you want. There is a similar mechanism on windows, but I haven't had time to look at it yet: I wanted to make a unified architecture for this kind of things.

Michael.

In our previous episode, Michael Van Canneyt said:

I think Ales was at some point working on having a common kevent +inotify support unit. (Kevent is the OSX/BSD variant)

Really ? Maybe it could be added to the fcl-base ?

Michael.

If so, make sure to make it a separate unit and enable this unit in fpmake.pp for the supported targets only, because I don't think that such a functionality exists for OS/2 (not even mentioning other targets supporting fcl-base like go32v2)...

Tomas

In our previous episode, Tomas Hajny said:

I think that was what it stalled on. Ales not wanting to abstract windows at that time.

IMHO packages in FCL should at least support the core platforms.

I will have a 's on my todo anyway.
If Ales has a OSX/BSD variant, then that would be helpful.

Michael.

And which database you prefer? I don't need complicated functionality. The most important is insert speed and it must be embedded. I'm thinking of SQLight, DBF or Firebird Embedded

Michael Van Canneyt wrote

There is a similar mechanism on windows, but I haven't had time to look at it yet: I wanted to make a unified architecture for this kind of things.

I created a truly single source cross-platform system for this. Register your interest (file, directory or everything), and a background thread does the work freeing up your UI. I don't use any OS specific API's, and it is still fast.

Regards,
- Graeme -

Krzysztof wrote

And which database you prefer? I don't need complicated functionality. The most important is insert speed and it must be embedded. I'm thinking of SQLight, DBF or Firebird Embedded

I'd probably go with SQLite or Firebird embedded.

SQlite is probably a bit easier to deploy and e.g. available on OSX by default anyway... however, I like Firebird's features and the fact that you can change to a client/server setup without changing code. So it depends on your requirements.

These calls are available in the linux unit. I have an article that describes how it works, if you want.

@Michael Van Canneyt: Could you send mi link to this article?