Re: psql: Buggy interactions with wraparound in maximized gnome terminals.

[Tomas Zubiri]

>(I don't think the OP specified which readline and/or Postgres version
he was using.)
That would be postgres 12.1 and readline 7

Tomas Zubiri
Software Developer
Cel: +54 911 5891 8239

El sáb., 21 de dic. de 2019 a la(s) 18:41, Tom Lane
(address@hidden) escribió:
>
> Chet Ramey <address@hidden> writes:
> > On 12/20/19 4:48 PM, Tomas Zubiri wrote:
> >> This is probably hard to reproduce, but I entered a state where the
> >> command I was writing was wrapping around at the 81st character while
> >> in full screen,  and the 1st character was being overwritten.This did
> >> not affect the command sent to the server, but I would not have a way
> >> to see what command I just entered.
>
> > It seems like the readline SIGWINCH handler, which causes it to update its
> > idea of the screen dimensions, isn't being called. I can't reproduce this
> > using readline and bash, and I don't know what postgres does with its
> > signal handling, or how it configures readline's signal handling (I assume
> > it doesn't do anything special).
>
> We don't touch SIGWINCH at all, so if readline sets up a handler for that,
> it ought to behave as expected.
>
> I notice though that we do this just before each readline() call:
>
>         /*
>          * Some versions of readline don't notice SIGWINCH signals that arrive
>          * when not actively reading input.  The simplest fix is to always
>          * re-read the terminal size.  This leaves a window for SIGWINCH to be
>          * missed between here and where readline() enables libreadline's
>          * signal handler, but that's probably short enough to be ignored.
>          */
> #ifdef HAVE_RL_RESET_SCREEN_SIZE
>         rl_reset_screen_size();
> #endif
>
> Is it conceivable that that bollixes things somehow, on some builds?
> (I don't think the OP specified which readline and/or Postgres version
> he was using.)
>
>                         regards, tom lane