clone - Opens a major and minor device pair on a STREAMS
The clone driver is a "pass through" device driver that
allows other drivers to select unique minor device numbers
on each open. In effect, the driver passes an open operation
through to the other driver. This mechanism allows
for multiple instantiations of a driver through a single
file system node.
The name parameter specifies the name of the special
device driver to be opened. The clone driver calls the
open routine of the other driver with flags that specify a
clone open, and sets up the new instantiation using the
returned major/minor pair. The new major number is the
minor number of the clonable entry, and the minor number
has been dynamically selected.
If the clone driver has an invalid minor number, or if the
driver indicated is not a clonable driver, an error
The master devices for pseudoterminals are examples of
clonable drivers (see the pty(7) reference page).
Functions: fstat(2), open(2)
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