Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > gnu.bash.bug > #15468

Re: bash sets O_NONBLOCK on pts

Show key headers only | View raw

2019-10-03 13:58:40 -0400, Chet Ramey:
> On 10/2/19 11:38 AM, Stephane Chazelas wrote:
> 
> > BTW, what's the point of the check_dev_tty() function? It seems
> > it just attempts to open the tty (the controlling one or the one
> > open on stdin), closes it, but doesn't return anything about the
> > success of failure in doing so.
> 
> It's to make up for an old bug that's probably gone everywhere. Back
> in the day, there were systems and services that would start interactive
> shells without a controlling terminal. Opening and closing /dev/tty
> forced the controlling terminal to be allocated.
[...]

Thanks.

I suspected it may be something like that. Though I thought,
without actually double-checking it, that the rest of the code
would end up opening the terminal device (without O_NOCTTY) anyway.

It may be worth adding a comment to document that purpose of the
function, and maybe rename it to something like
control_tty_if_not_already_controlled or something that more
accurately describes its intent.

-- 
Stephane

Back to gnu.bash.bug | Previous | Next | Find similar | Unroll thread

Thread

Re: bash sets O_NONBLOCK on pts Stephane Chazelas <stephane.chazelas@gmail.com> - 2019-10-03 19:23 +0100

csiph-web