[fpc-pascal] FPC_HAS_FEATURE_TEXTIO - Strange behaviour!

[Marco van de Voort]

In our previous episode, SirStorm25 said:
> 
> Nooo!!!!!
> What are these functions meant to do?
> This seems way more harder than it looks!

Well that is not that hard:

 do_read - read bytes from file
 do_write - write bytes to file
 do_close - close file
 do_erase - open file
 do_rename - rename file

etc.

_BUT_ the devil is in the details, most notably you must wrap the
errorhandling of your OS to match FPC's (which is a bit doslike). 

For this, take the RTL of any OS you are familiar with, and study it.