old-style compatibility pseudo-terminal driver
pty driver provides support for the traditional BSD
naming scheme that was used for accessing pseudo-terminals before it was
traditional naming is still used in Linux. When the device
/dev/ptyXX is being opened, a new terminal shall be
created with the
driver. A device node for this terminal shall be created, which has the name
pty driver also provides a cloning
System V /dev/ptmx device.
New code should not try to allocate pseudo-terminals using this
interface. It is only provided for compatibility with older C libraries that
tried to open such devices when
was being called, and for running Linux binaries.
The BSD-style compatibility pseudo-terminal driver uses the following device
A pseudo-terminal driver appeared in 4.2BSD.
Unlike previous implementations, the master and slave device nodes are destroyed
when the PTY becomes unused. A call to
a nonexistent master device will already cause a new master device node to be
created. The master device can only be destroyed by opening and closing it.
- Pseudo-terminal master devices.
- Pseudo-terminal slave devices.
- Control device, returns a file descriptor to a new master pseudo-terminal
pty driver cannot be unloaded, because
it cannot determine if it is being used.