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Re: curl_off_t suffix

From: Jamie Lokier <>
Date: Thu, 14 Aug 2008 10:25:55 +0100

Dan Fandrich wrote:
> #define INT64_C(x) (x + (INT64_MAX - INT64_MAX))

I wonder why they did that??!

If x is a large constant, how is that (123456789012345 + (INT64_MAX -
INT64_MAX)) is acceptable to the compiler (note no suffix on the
constant), but simply the constant by itself, or ((__int64_t)
123456789012345), are not?

Based on that:

> Boy, that's going to be fun to parse in m4! It may be easier to parse
> INT64_MAX instead and extract the suffix; Watcom defines that as a simple
> #define INT64_MAX 9223372036854775807LL
> but, surely, that's in itself no more portable.

I wouldn't be surprised to find some things define it as
((int64_t) 9223372036854775807) or similar.

-- Jamie
Received on 2008-08-14