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From: chris@mimsy.umd.edu (Chris Torek)
Newsgroups: comp.lang.c
Subject: Re: Question: Floating point and printf()
Message-ID: <21258@mimsy.umd.edu>
Date: 13 Dec 89 06:10:20 GMT
References: <2777@cbnewsj.ATT.COM>
Distribution: na
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 24

In article <2777@cbnewsj.ATT.COM> asd@cbnewsj.ATT.COM (adam.denton) writes:
>I would like to know what the CORRECT format specifier is in printf()
>to print out values of type `float' and values of type `double'.

`%e', `%f', and `%g'.

>According to K&R2, page 244, the format specifiers e, f, and g all default
>to type `double'.  K&R2 does not mention the use of the `l' (lower case ell)
>in regard to floating point.

K&R2 does, however, mention (possibly elsewhere) that it is NOT POSSIBLE
to pass a `float' to a variadic function.  All such values are converted
to double precision in the absence of a prototype, or in the presence of
a variadic prototype.

>Now in the Turbo C 2.0 reference manual under ...printf(), it is mentioned
>that the letter ell can be prefixed to e, f, or g to indicate that the
>argument is type `double.'

... which is incredibly misleading, since the letter ell can be omitted
to indicate that the argument is type double as well.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@cs.umd.edu	Path:	uunet!mimsy!chris