Improve missing tty handling in init(8)
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Authored by trasz on Feb 10 2018, 8:24 PM.

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imp

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manpages

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rS330054: Improve missing tty handling in init(8). This removes a check that did

Summary

Improve missing tty handling in init(8). This removes a check that did nothing - it was checking for ENXIO, which, with devfs, is no longer returned - and was badly placed anyway, and replaces it with similar one that works, and is done just before starting getty, instead of being done when rereading ttys.

From the practical point of view, this makes init(8) handle disappearing terminals (eg /dev/ttyU*) gracefully, without unneccessary getty restarts and resulting error messages.

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rS FreeBSD src repository - subversion

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Event Timeline

trasz created this revision.Feb 10 2018, 8:24 PM

Herald added a subscriber: imp. · View Herald TranscriptFeb 10 2018, 8:24 PM

Harbormaster completed remote builds in B14943: Diff 39158.Feb 10 2018, 8:24 PM

trasz edited the summary of this revision. (Show Details)Feb 10 2018, 8:25 PM

trasz added a reviewer: imp.

Don't check if the device node exists for entries marked "on", as opposed to "onifexists" and "onifconsole".

Herald added a reviewer: manpages. · View Herald TranscriptFeb 26 2018, 2:25 PM

Harbormaster completed remote builds in B15275: Diff 39745.Feb 26 2018, 2:25 PM

imp accepted this revision.Feb 26 2018, 9:00 PM

This revision is now accepted and ready to land.Feb 26 2018, 9:00 PM

jilles added a subscriber: jilles.Feb 26 2018, 10:39 PM

jilles added inline comments.

lib/libc/gen/getttyent.3
121 ↗	(On Diff #39745)	typo: neccessarily should be necessarily
sbin/init/init.c
1517–1522 ↗	(On Diff #39745)	Is it indeed deliberate that this is an `open()` and not just a `stat()` or `eaccess()`?

Closed by commit rS330054: Improve missing tty handling in init(8). This removes a check that did (authored by trasz). · Explain WhyFeb 27 2018, 10:54 AM

This revision was automatically updated to reflect the committed changes.

trasz marked an inline comment as done.Feb 27 2018, 10:58 AM

trasz added inline comments.

lib/libc/gen/getttyent.3
121 ↗	(On Diff #39745)	Good catch, fixed. Thanks!
sbin/init/init.c
1517–1522 ↗	(On Diff #39745)	In theory this should be access(2), yeah. But in my testing the open(2) seems to work a bit better. Can't really explain it, but with access(2) you get false positives (zero return) every five attempts. In other words, I've been repeatedly plugging the USB serial dongle in and out, and with access(2) it seems to sometimes restart getty even when it shouldn't.