From:	CSBVAX::MRGATE!RELAY-INFO-VAX@CRVAX.SRI.COM@SMTP 11-SEP-1988 13:10
To:	ARISIA::EVERHART
Subj:	Re: VAXC format flags


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Date:    Sun, 11 Sep 88 09:17:36 PDT
From:     nagy%warner.hepnet@LBL.Gov (Frank J. Nagy, VAX Wizard & Guru)
Message-Id: <880911091736.21a036a0@LBL.Gov>
Subject: Re: VAXC format flags
To:       Info-VAX@kl.sri.com
X-ST-Vmsmail-To: INFO_VAX

> The file SYS$HELP:VAXC023.RELEASE_NOTES informs me of, among other
> things, "... the addition of three new format flags (#, +, space) and
> the following new format specifiers: i, p, and n" for the printf and scanf
> functions.  We received our C RTL documentation only recently and yet it
> doesn't contain explanations of these format flags and specifiers.  How
> can I find out what they do???
     
They are documented in the V2.4 Release Notes for VAX C.  Here is a
short explanation cribbed from same:

n	conversion specifier like %d except no input is consumed.
	The argument corresponding to %n must be pointer to integer
	into which is written the number of characters read from the
	input stream by this point in the fscanf call.

p	conversion specifier for input/output.  %p by fprintf outputs
	the value of a pointer in an implementation-defined manner.
	For fscanf, returns the pointer value back to an argument which
	should be a pointer to a pointer to void.

-, +, space, and #

	conversion flags between the "%" and the conversion specifier.

	"-" specifies left justification.
	"+" specifies signed conversion with an explicit sign always
	    present
	" " requests a space to appear before the result
	"#" requests the result to be converted to an alternate form
	    depending on the conversion done:

	    o  the first digit will always be zero.

	    x  Prepends 0x

	    e,E,f,F,g,G
	       result will always contain a decimal point


= Frank J. Nagy   "VAX Guru & Wizard"
= Fermilab Research Division EED/Controls
= HEPNET: WARNER::NAGY (43198::NAGY) or FNAL::NAGY (43009::NAGY)
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