[avr32-libc-devel] FW: Structure of error numbers

[Boyapati, A. <Ani...@at...>]

( Communication for archival)

-----Original Message-----
From: Boyapati, Anitha 
Sent: Thursday, March 11, 2010 2:04 PM
To: Kaushik, Praveen_Kumar; Gupta, Usha
Cc: Praveen, Vidhya; Singh, Abnikant
Subject: RE: Structure of error numbers


>    In avr-libc, an integer variable is taken in errno.h and sets it
> whereas in NewLib a reentrant structure is taken which is having an
> integer variable for error number. How do we have to do in avr32-libc?
> 


Including a global variable as required by ANSI C is a much simpler way of implementing error handling. However, when it comes to avr32-libc, I recommend making errno reentrant. I took a quick glance at newlib sources. Making errno reentrant avoids undefined behavior during racing conditions.

FYI- Several multi-threaded applications are built and run on AVR32 (mostly UC3A) with/without linux OS support. Thread-safe implementation of avr32-libc is highly recommended wherever applied (just not limited to error handling case)

Anitha