Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!mcsun!unido!tub!net
From: net@tub.UUCP (Oliver Laumann)
Newsgroups: comp.lang.c
Subject: Math library functions and error checking
Message-ID: <1323@tub.UUCP>
Date: 4 May 90 10:40:27 GMT
Reply-To: net@tub.UUCP (Oliver Laumann)
Organization: Technical University of Berlin, Germany
Lines: 11

What is the correct method to check whether an exception (overflow,
invalid arguments, etc.) occurred during the execution of a C math
library function (such as sqrt() or sin())?

Do I have to test the result against NaN, or do I have to check errno
(EDOM)?  If the latter is true, is errno cleared automatically on
success or do I have to clear it before calling the function?

Thanks,
--
Oliver Laumann     net@TUB.BITNET     net@tub.cs.tu-berlin.de     net@tub.UUCP