Re: [musl] print does not support variable width plus padding

[Rich Felker <dalias@libc.org>]

On Wed, Dec 15, 2021 at 01:37:43PM -0500, Andrew Snyder wrote:
> That is probably true but I think on accident trying to replicate my
> original issue which was using the native function

With the program:

#include <stdio.h>
int main(int argc, char **argv)
{
	printf("%0*i\n", 2, argc);
}

(written using argc so it can't be collapsed to a constant string at
compile time) I get output of "01\n" as expected. If you think there's
a bug in musl for this or related functionality, can you provide a
minimal C test case?

> On Wed, Dec 15, 2021 at 1:09 PM Quentin Rameau <quinq@fifth.space> wrote:
> 
> > Hi Andrew,
> >
> > > Sorry accidentally sent before attaching this
> > >
> > > ~# docker run -it --rm alpine /bin/ash
> > > / # /lib/libc.musl-x86_64.so.1
> > > musl libc (x86_64)
> > > Version 1.2.2
> > > Dynamic Program Loader
> > > Usage: /lib/libc.musl-x86_64.so.1 [options] [--] pathname [args]
> > > / # printf %0*i 2 1
> > > ash: %0*i: invalid format
> >
> > This looks like you found a bug in Busybox printf implementation.

FWIW I suspect the problem is that Busybox is not recognizing the 0
character as a flag (which it is, in the printf grammar) and thinks
it's the leading character of a width, making the * specifier for
width invalid (since a width was already seen).

Rich