Re: pending signal after rl_callback_read_char

[Chet Ramey]

On 9/20/22 3:13 PM, Simon Marchi wrote:
> > It could be a timing issue: the signal arrives after rl_callback_read_char
> > checks for it and before it returns, but there's not a lot it can do about
> > that. That's why we have rl_check_signals() now.
>
> That's what I think, there's a window in rl_callback_read_char after the
> last time rl_check_signals was called, but before the original (user's)
> signal handlers are put back in place.  If the SIGINT arrives during
> that window, it will go unnoticed until the next call to
> rl_callback_read_char (or some other readline function).

        [...]

> I think that it could be fixed in readline by doing the following when
> reinstalling the old signal handlers:
>
>   - block signals
>   - call RL_CHECK_SIGNALS
>   - restore old handlers
>   - unblock signals

That's more of a change than I'm willing to make before readline-8.2 is
released. In the meantime, you could look at rl_persistent_signal_handlers,
which, in theory, should work on readline versions >= 7.0.

Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/