What does this enum declaration in C mean?

Question

I am trying to understand some C code in a legacy database. There are constructions there of the form:

enum {a=0,b,c,d};

What does this achieve ? In the manuals, I only see constructions of the form:

enum example{a=0,b,c,d} test1; and this I understand.

Thanks, Suresh

score 6 · Answer 1 · answered Mar 02 '15 at 03:57

6

This defines a set of constants which may be used anywhere with the values

Since we worried less about type safety in legacy C applications, we don't need a specific type for this, or variables directly associated with it

answered Mar 02 '15 at 03:57

James McLeod

The question is better suited to SO than to Programmers. – James McLeod Mar 02 '15 at 04:04
1

Enumeration constants are always of type `int`. – Keith Thompson Mar 02 '15 at 04:48
Not quite http://stackoverflow.com/questions/366017/what-is-the-size-of-an-enum-in-c – James McLeod Mar 02 '15 at 14:02
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Yes, quite. The size of an enumeration *type* is implementation-defined. The *constants* are always of type `int`. – Keith Thompson Mar 02 '15 at 15:11
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@KeithThompson this is a slightly late response, I confess. Thank you for pointing out that subtle difference; I only clued into what you mean on rereading these comments today. – James McLeod Dec 18 '18 at 04:19

1 Answers1