bug#80745: fmt --width arbitrary limit?

On 04/04/2026 22:18, Karl Berry wrote:
> I ran
>    echo in | fmt -w 9999 >/tmp/out
> and was surprised to get the error:
>    fmt: invalid width: '9999': Numerical result out of range
> 
> Why is it fmt's business to decide what value is acceptable?
> Does POSIX require this arbitrary limit?
> I don't see the limit documented in coreutils.texi or fmt --help.
> 
> This is with fmt (GNU coreutils) 8.32. Sorry if it is fixed in a newer
> release.
> 
> Rationale: I was using fmt as a quick way to concatenate a bunch of
> short lines into one. I am aware there are many other ways to do it. -k

 From the code:

/* FIXME: Remove these arbitrary limits.  */#define MAXWORDS        1000
#define MAXCHARS        5000

-w is limited to MAXCHARS/2

thanks,
Padraig.