pts man page on HP-UX

Man page or keyword search:  
man Server   10987 pages
apropos Keyword Search (all sections)
Output format
HP-UX logo
[printable version]

pts(7)									pts(7)

NAME
       pts - STREAMS slave pty (pseudo-terminal) driver

SYNOPSIS
DESCRIPTION
       A pseudo-terminal (pty) consists of a tightly-coupled pair of character
       devices, called the master device and slave device.  The pty master and
       slave  device  drivers  work together to simulate a terminal connection
       where the master provides a connection to the  pseudo  terminal	server
       process	and  the  slave provides a terminal device special file access
       for the terminal application processes, as depicted below:

				----------------
			       | pty functions	|
	      Application <--> |----------------| <--> Server
	       Processes       | Slave | Master |	Process
			       | (pts) | (ptm)	|
				----------------

       The slave driver, with (STREAMS pty emulation module) and (STREAMS line
       discipline module) pushed on top (not shown for simplicity), provides a
       terminal interface as described in  termio(7).	Whereas	 devices  that
       provide	the  terminal interface described in termio(7) have a hardware
       device behind them; in contrast, the slave device has  another  process
       manipulating  it	 through  the master side of the pty.  Data written on
       the master device is given to the slave device as input and data	 writ‐
       ten on the slave device is presented as input on the master device.

       In  order  to  use the STREAMS pty subsystem, a node for the master pty
       driver and N number of slave pty devices must be installed (see	ptm(7)
       for more details on master pty).	 When the master device is opened, the
       corresponding slave device is automatically locked out.	 No  user  can
       open that slave device until its permissions are changed (via the func‐
       tion) and the device is unlocked (via the  function).   The  user  then
       call the function to obtain the name of the slave device and invoke the
       system call to open the	slave  device.	 Although  only	 one  open  is
       allowed	on  a  master  device, multiple opens are allowed on the slave
       device.	After both the master and slave have been opened, the user has
       two  file  descriptors  which represent the end points of a full duplex
       connection composed of two streams that are automatically connected  by
       the  master  and slave devices when they are opened.  The user may then
       push the desired modules (for example, and on  for  terminal  semantics
       and on for Packet Mode feature).

       The  master  and slave drivers pass all STREAMS messages to their adja‐
       cent drivers.  Only the message needs some special  processing  because
       the  read  queue	 of  the master is connected to the write queue of the
       slave and vice versa.  For example, the flag is	changed	 to  flag  and
       vice  versa  whenever  a	 message travels across the master−slave link.
       When the master device is closed, an message is sent to the correspond‐
       ing  slave  device  which  will render that slave device unusable.  The
       process on the slave side gets the errno when attempting a system  call
       to the slave device file but it will be able to read any data remaining
       in the slave stream.  Finally, when all the data	 has  been  read,  the
       system  call  will return 0, indicating that the slave can no longer be
       used.  On the last close of the slave device, a zero-length message  is
       sent  to	 the corresponding master device.  When the application on the
       master side issues a read(2) or getmsg(2) system calls, a 0  (zero)  is
       returned.  The user of the master device may decide to close the master
       device file, which dismantles the stream on the master  side.   If  the
       master  device  remains	opened,	 the corresponding slave device can be
       opened and used again by another user.

EXAMPLES
       The following example shows how a STREAMS pty master and slave  devices
       are typically opened.

AUTHOR
       was developed by HP and OSF.

FILES
       Streams pty master clone device
       Streams pty slave devices (0 <=
			 N  < where is a kernel tunable parameter which can be
			 changed via SAM (see sam(1M)).

SEE ALSO
       insf(1M), sam(1M), getmsg(2),  ioctl(2),	 open(2),  read(2),  write(2),
       grantpt(3C),  ptsname(3C),  unlockpt(3C),  ldterm(7),  ptem(7), ptm(7),
       streamio(7), termio(7).

									pts(7)
[top]

List of man pages available for HP-UX

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net