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From: williams@beowulf.ucsd.edu (Paul Williamson)
Newsgroups: comp.std.c
Subject: printf zero-pads strings?
Message-ID: <7279@sdcsvax.UCSD.Edu>
Date: 21 Oct 89 23:52:30 GMT
Sender: nobody@sdcsvax.UCSD.Edu
Reply-To: williams@beowulf.UCSD.EDU (Paul Williamson)
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Organization: EE/CS Dept. U.C. San Diego
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Has the definition of printf changed since early drafts of the ANSI spec?
In particular, I am interested in the interpretation of 
  printf("%05s", "x");
According to my old draft spec, and several compilers, this should print
"0000x".  That is, it should pad the string on the left with zeroes.  But
K&R2 and several other compilers give "    x", claiming that zero-padding
applies only to numeric values.

I know from my experiments with various compilers that it isn't safe to
use this construct in the real world.  But I can't help but wonder which
compilers are right according to the current pANS.  Language lawyers?

Paul Williamson           williams%cs@ucsd.edu