PTM(4) | Device Drivers Manual | PTM(4) |
ptm
—
pseudo-device pty
ptm
driver is the backend for the
/dev/ptm device. It supports three
ioctl(2)s. The first is
TIOCPTMGET
, which allocates a free pseudo-terminal
device, sets its user ID to the calling user,
revoke(2)s it, and returns the
opened file descriptors for both the master and the slave pseudo-terminal
device to the caller in a struct ptmget. This struct has
the following content:
struct ptmget { int cfd; int sfd; char cn[PATH_MAX]; char sn[PATH_MAX]; };
where cfd and sfd contain the master resp. slave device's file descriptor and cn and sn the corresponding paths in the file system.
The /dev/ptmx device supports two more
ioctl(2)s,
TIOCGRANTPT
, which is used by
grantpt(3),
TIOCPTSNAME
, which is used by
ptsname(3).
The ptm
device is included with the
pseudo-device pty(4). It can be
disabled by adding “options
NO_DEV_PTM
” to the kernel configuration.
ptm
access deviceptm
cloning device, used to implement Unix98
ptysNovember 30, 2013 | NetBSD 9.4 |