|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
|
NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | HISTORY | SEE ALSO | COLOPHON |
|
|
|
TIOCPKT(2const) TIOCPKT(2const)
TIOCPKT, TIOCGPKT, TIOCSPTLCK, TIOCGPTLCK, TIOCGPTPEER -
pseudoterminal ioctls
Standard C library (libc, -lc)
#include <asm/termbits.h> /* Definition of TIOC* constants */
#include <sys/ioctl.h>
int ioctl(int fd, TIOCPKT, const int *mode);
int ioctl(int fd, TIOCPKT, int *mode);
int ioctl(int fd, TIOCSPTLCK, const int *lock);
int ioctl(int fd, TIOCGPTLCK, int *lock);
int ioctl(int fd, TIOCGPTPEER, int flags);
TIOCPKT
Enable (when *mode is nonzero) or disable packet mode. Can
be applied to the master side of a pseudoterminal only (and
will return ENOTTY otherwise). In packet mode, each
subsequent read(2) will return a packet that either
contains a single nonzero control byte, or has a single
byte containing zero ('\0') followed by data written on the
slave side of the pseudoterminal. If the first byte is not
TIOCPKT_DATA (0), it is an OR of one or more of the
following bits:
TIOCPKT_FLUSHREAD The read queue for the
terminal is flushed.
TIOCPKT_FLUSHWRITE The write queue for the
terminal is flushed.
TIOCPKT_STOP Output to the terminal
is stopped.
TIOCPKT_START Output to the terminal
is restarted.
TIOCPKT_DOSTOP The start and stop
characters are ^S/^Q.
TIOCPKT_NOSTOP The start and stop
characters are not
^S/^Q.
While packet mode is in use, the presence of control status
information to be read from the master side may be detected
by a select(2) for exceptional conditions or a poll(2) for
the POLLPRI event.
This mode is used by rlogin(1) and rlogind(8) to implement
a remote-echoed, locally ^S/^Q flow-controlled remote
login.
TIOCGPKT
Return the current packet mode setting in the integer
pointed to by mode.
TIOCSPTLCK
Set (if *lock is nonzero) or remove (if *lock is zero) the
lock on the pseudoterminal slave device. (See also
unlockpt(3).)
TIOCGPTLCK
Place the current lock state of the pseudoterminal slave
device in the location pointed to by lock.
TIOCGPTPEER
Given a file descriptor in fd that refers to a
pseudoterminal master, open (with the given open(2)-style
flags) and return a new file descriptor that refers to the
peer pseudoterminal slave device. This operation can be
performed regardless of whether the pathname of the slave
device is accessible through the calling process's mount
namespace.
Security-conscious programs interacting with namespaces may
wish to use this operation rather than open(2) with the
pathname returned by ptsname(3), and similar library
functions that have insecure APIs. (For example, confusion
can occur in some cases using ptsname(3) with a pathname
where a devpts filesystem has been mounted in a different
mount namespace.)
On success, 0 is returned. On error, -1 is returned, and errno is
set to indicate the error.
ENOTTY
TIOCGPKT
Linux 3.8.
TIOCGPTLCK
Linux 3.8.
TIOCGPTPEER
Linux 4.13.
The BSD ioctls TIOCSTOP, TIOCSTART, TIOCUCNTL, and TIOCREMOTE have
not been implemented under Linux.
ioctl(2), ioctl_tty(2)
This page is part of the man-pages (Linux kernel and C library
user-space interface documentation) project. Information about
the project can be found at
⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report
for this manual page, see
⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
This page was obtained from the tarball man-pages-6.15.tar.gz
fetched from
⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
2025-08-11. If you discover any rendering problems in this HTML
version of the page, or you believe there is a better or more up-
to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not
part of the original manual page), send a mail to
man-pages@man7.org
Linux man-pages 6.15 2025-05-17 TIOCPKT(2const)
Pages that refer to this page: ioctl_tty(2)
|
HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|