From: Andrew Gibson <andrew AT petrologic DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: printf 'g' conversion
Date: Mon, 02 Mar 1998 12:45:17 +0000
Message-ID: <34FAA9D8.CF1A4A39@petrologic.co.uk>
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I've also noticed a couple of other differences in printf between DJGPP
and Linux:

1. printf("%9.6g",99999.9999);

displays '100000.' in Linux but '100000.0' in DJGPP.
I think Linux may be correct here but I haven't fixed this one.

2. printf("%1.1f",0.00123);

displays '-0.0' in Linux but '0.0' in DJGPP.
I hate seeing '-0' so I think DJGPP is better here.

Here is the patch for the printf 'g' conversion modification.

File: libc/ansi/stdio/doprnt.c

479a480,481
>   int doextradps=0;    /* Do extra decimal places if the precision
needs it */
>   int doingzero=0;     /* We're displaying 0.0 */
526a529,535
>   /* If integer is zero then we need to look at where the sig figs are
*/
>   if (integer<1) {
>         /* If fract is zero the zero before the decimal point is a sig
fig */
>         if (fract==0.0) doingzero=1;
>         /* If fract is non-zero all sig figs are in fractional part */

>         else doextradps=1;
>   }
663,665c672,680
<     /* a precision of 0 is treated as a precision of 1. */
<     if (!prec)
<       ++prec;
---
>     if (prec) {
>         /* If doing zero and precision is greater than 0 count the
>          * 0 before the decimal place */
>         if (doingzero) --prec;
>     }
>     else {
>         /* a precision of 0 is treated as precision of 1 unless doing
zero */
>         if (!doingzero) ++prec;
>     }
710c725,731
<       prec--;
---
>       /* If we're not adding 0s
>        * or we are but they're sig figs:
>        * decrement the precision */
>       if ((doextradps!=1) || ((int)tmp!=0)) {
>         doextradps=0;
>         prec--;
>       }