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Date: Thu, 17 Oct 1996 19:21:48 +1000
From: Andrew McRae <amcrae@cisco.com>
Message-Id: <199610170921.TAA25379@metaplex-ss10.cisco.com>
To: phk@freebsd.org, hackers@freebsd.org
Subject: Re: enum considered bad ?
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phk@critter.tfs.com (Poul-Henning Kamp):
> 
> I've noticed that "enum" is hardly ever used in C programs, is this
> because people consider it a bad idea or because they havn't really
> got the swing of it ?

Can be historical in nature. Enums came in around the same
time that structure copying came in, so the earliest kernels
and user-land code did not have any enum code in them.

In kernel stuff, one reason why #define stuff is preferred
over enums is because you can use them in asm files.
Also, people sometimes like to overload variables with
bit masks as well as enumeration.

I use enums where I can, and they are encouraged here at cisco.
I prefer them because the compiler can be a little stricter
with type checking and switch warnings etc., but it is
surprising how many times you want to store those numbers
in a char (so you can't declare the variable as an enum) or
get at them in an assembler routiner.

> Poul-Henning Kamp           | phk@FreeBSD.ORG       FreeBSD Core-team.

Cheers,
Andrew McRae (cisco Core Down Under).