[fpc-devel] libc translations

[Daniël Mantione]

Op Sun, 10 Aug 2008, schreef Boian Mitov:

>   Hi Daniel,
>
> Thank you!
> As I mentioned I am very new, and still don't know the exact rules of the 
> purpose of specific units. I am not sure if the timers are available on other 
> systems than Linux yet. I am sure there is some form of equivalent. I 
> actually don't have any Kylix code.

In Free Pascal we have spread the functionality over multiple units:
- "baseunix" contains Unix system calls that are portable accross Unixes.
- "unix" contains generally available Unix routines that are portable
    accross Unixes:
- "linux" contains Linux specific system calls.

If the HR timers are not part of any standard, implementing them in 
"linux" seems the best approach to me.

> I am porting Windows code, actually making it cross platform as we 
> support Delphi 5-2007, and plan to support Lazarus for Windows and Linux 
> for now, and hopefully for other platforms in the future. Porting huge 
> code from Windows is slow and error prone process, so I am doing it in 
> stages. For now I have made everything to recompile under Lazarus in 
> Linux, and now I am filling the items I had to cut from the code during 
> the conversion. In Windows I use the Media Timers, and the only 
> equivalent thing I have found in Linux is the High Resolution timers. I 
> have been studding the FPC and Lazarus code, and I discovered the libc, 
> and it seemed as the logical place such timers to be implemented. If 
> they belong to a different location, this is fine. I can also keep them 
> in my code, but I thought other people can benefit from the translation.

Timing on Unix is often done using alarm/setitimer system calls, 
gettimeofday, etc. I don't know wether these satisfy your needs.

> As I said I am days fresh on Linux, and have been playing with Lazarus and 
> FPC under Windows for only a month or so, and I have a lot to learn ;-) . I 
> was able however to get the libraries to work nearly 80% already, and I think 
> in few months can have them ready for deployment. I still will have to figure 
> out how to package them in Linux, and how to deploy them compiled against 
> different visual frameworks, but that is for the future. For now I am focused 
> on getting the high resolution timers to work, so I can move to the next 
> issue in the list ;-) .

Good to hear that you are making progress!

Daniël