multiple devpts mounts not supported in sysdeps/unix/sysv/linux/ptsname.c:_ptsname_internal()

[Andreas Schwab]

"Serge E. Hallyn" <serge.hallyn@canonical.com> writes:

> grantpt, ptsname, and ptsname_r make use of _ptsname_internal().  That
> function works by appending the TIOCGPTN result to "/dev/pts".  The
> path /dev/pts is hardcoded.  That means that if you call grantpt on an
> fd from /chroot/dev/pts, and /dev/pts/0 (for instance) does not exist
> on the host, you'll (wrongly) get back an error.  This has been seen with
> libvirt (and is easly to verify with a simple testcase).

If you want to use /dev/pts from the chroot you must run grantpt in the
chroot.  Since getpt or posix_openpt always returns an fd from the
system /dev/pts this is not an unreasonable restriction.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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