| ZFD(4D) | Devices | ZFD(4D) |
zfd — Zone file
descriptor driver
The zfd character driver exports devices
into the zone which can be used by a a standalone process within the zone as
stdin, stdout, and
stderr. The zfd driver behaves
in a similar manner as the zcons(7D) device. Inside
a zone, the subsidiary side devices appear as
/dev/zfd/[0-4].
The zone's zfd device configuration is driven by
zoneadmd and a zone attribute
zlog-mode which is somewhat of a misnomer since its
purpose has evolved. The attribute can have a variety of values, but the
lowest two positions in the value string are used to control how many zfd
devices are created inside the zone and if the primary stream is a tty.
---nt-tnWith the t flag set,
stdin, stdout, and
stderr, are multiplexed onto a single full-duplex
stream which is configured as a tty. That is, ptem,
ldterm and ttycompat are
autopushed onto the stream when the subsidiary side is opened. There is only
a single zfd device (0) needed for the primary stream.
When the n flag is set, it is assumed that
output logging will be done within the zone itself. In this configuration 1
or 2 additional zfd devices, depending on tty mode
(t
flag), are created within the zone. An application
can then configure the zfd streams driver into a multiplexer. Output from
the stdout/stderr zfd(s) will be teed into the correspond logging zfd(s)
within the zone.
| October 16, 2015 | OmniOS |