[fpc-pascal] Access GPIO pins on RPi2 without root?

Jonas Maebe jonas.maebe at elis.ugent.be
Wed Oct 7 13:32:08 CEST 2015


Bo Berglund wrote on Wed, 07 Oct 2015:

> I think that it really does because there must be some interface
> between the FPC system and the underlying operating system managing
> the hardware.

On Linux/Unix, every interface to hardware gets exposed as a file  
(generally under /dev). Sometimes you have libraries that provide a  
higher level interface, but in the end it will always access that  
file. If you need root permissions to perform actions on this file  
with language X, you will also need them with language Y and also if  
you use library Z to access it. The file operations are basic POSIX  
operations (open, read, write, ioctl, close), which are available with  
an "fp" prefix via the baseunix and unix units, and which are the same  
in C or other languages.

If you have a library that you want to use, then you can of course ask  
here whether anyone has translated the headers for it (which will  
probably be in C) to Pascal or so.


Jonas



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