[bmake] bmake sigint handling causing tty corruption

[Poul-Henning Kamp]

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In message <20170718205700.GA2131 at hades.panopticon>, Dmitry Marakasov writes:


>In short, when FreeBSD ports options dialog is interrupted by Ctrl+C,
>there's chance of sporadic terminal corruption. They are not always
>reproducible and seem to be dependent on a machine, shell, terminal,
>tmux used, but are not tied to any specific configuration.

I've noticed another quirk which may be related:

Start vi(1) on some file.

Type
	!some_command_producing_significant_output | less

Ctrl-C

This leaves the less(1) alive and competing vi(1) for the terminal
in a most unworkable and annoying fashion.


-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.