This bug was discovered using the comms/mgetty+sendfax.
That port executes a system() call that has output redirected to /dev/console. That system() fails with the following message:
system() failed: Inappropriate ioctl for device
This error message is confirmed by the following command:
# echo "foo" >/dev/console 2>&1 </dev/null
/dev/console: Device not configured.
This program was working fine on FreeBSD 11.1-Release.
The box on which it is failing....Is a headless server in a closet that DOES NOT have a monitor attached.
I have another box running FreeBSD 11.2-Release, with a monitor attached, on which it appears to be working.
Maybe it depends on motherboard used.
I confirm this issue on this mainboard:
Manufacturer: Gigabyte Technology Co., Ltd.
Product Name: N3150ND3V
FreeBSD 12.0-RELEASE-p7 r349858 GENERIC amd64
Checked this case on different hardware and the same OS version. No problem occurred. With or without monitor on DSUB /dev/console is accessible.