Yes, I want to read the whole stdin in a single operation, so the -d was
there to disable stopping at newline
It seem that instead made read stop at null bytes
I worked around this limitation with:

xx=$(echo -e - a$'\000'b; echo .); xx=${xx[1,-2]}; echo -n - $xx
ab

but I will try also your suggestion, thanks

Pier Paolo Grassi


Il giorno gio 21 ott 2021 alle ore 15:08 Peter Stephenson <
p.w.stephenson@ntlworld.com> ha scritto:

> > On 21 October 2021 at 13:35 Pier Paolo Grassi <pierpaolog@gmail.com>
> wrote:
> > Hello, I just found out:
> >
> > echo -e - a$'\000'b | IFS='' builtin read -r -d '' xx; echo -n - $xx
> > result is "a"
> >
> > is it possible for builtin read not to stop an null bytes? I found
> nothing
> > in documentation.
> > thanks
>
> I think -d '' is telling it to treat NULL bytes as a delimiter.  Take that
> out.
>
> If you're not trying to read a line, don't use read.  If you "zmodload
> zsh/system"
> there's a sysread command which is more useful for lower level operations.
>
> pws
>