summaryrefslogtreecommitdiffstats
path: root/man7/pty.7
diff options
context:
space:
mode:
Diffstat (limited to 'man7/pty.7')
-rw-r--r--man7/pty.723
1 files changed, 13 insertions, 10 deletions
diff --git a/man7/pty.7 b/man7/pty.7
index 5d9b429..45cdb5f 100644
--- a/man7/pty.7
+++ b/man7/pty.7
@@ -2,7 +2,7 @@
.\"
.\" SPDX-License-Identifier: Linux-man-pages-copyleft
.\"
-.TH pty 7 2022-12-04 "Linux man-pages 6.05.01"
+.TH pty 7 2023-11-19 "Linux man-pages 6.7"
.SH NAME
pty \- pseudoterminal interfaces
.SH DESCRIPTION
@@ -13,7 +13,7 @@ One end of the channel is called the
.IR master ;
the other end is called the
.IR slave .
-.PP
+.P
The slave end of the pseudoterminal provides an interface
that behaves exactly like a classical terminal.
A process that expects to be connected to a terminal,
@@ -29,24 +29,24 @@ that is connected to the slave.
Conversely, anything that is written to the slave end of the
pseudoterminal can be read by the process that is connected to
the master end.
-.PP
+.P
Data flow between master and slave is handled asynchronously,
much like data flow with a physical terminal.
Data written to the slave will be available at the master promptly,
but may not be available immediately.
Similarly, there may be a small processing delay between
a write to the master, and the effect being visible at the slave.
-.PP
+.P
Historically, two pseudoterminal APIs have evolved: BSD and System V.
SUSv1 standardized a pseudoterminal API based on the System V API,
and this API should be employed in all new programs that use
pseudoterminals.
-.PP
+.P
Linux provides both BSD-style and (standardized) System V-style
pseudoterminals.
System V-style terminals are commonly called UNIX 98 pseudoterminals
on Linux systems.
-.PP
+.P
Since Linux 2.6.4, BSD-style pseudoterminals are considered deprecated:
support can be disabled when building the kernel by disabling the
.B CONFIG_LEGACY_PTYS
@@ -71,7 +71,7 @@ the name returned by
.BR ptsname (3)
in a call to
.BR open (2).
-.PP
+.P
The Linux kernel imposes a limit on the number of available
UNIX 98 pseudoterminals.
Up to and including Linux 2.6.3, this limit is configured
@@ -122,7 +122,10 @@ BSD master devices
BSD slave devices
.SH NOTES
Pseudoterminals are used by applications such as network login services
-.RB ( ssh "(1), " rlogin "(1), " telnet (1)),
+(\c
+.BR ssh (1),
+.BR rlogin (1),
+.BR telnet (1)),
terminal emulators such as
.BR xterm (1),
.BR script (1),
@@ -131,13 +134,13 @@ terminal emulators such as
.BR unbuffer (1),
and
.BR expect (1).
-.PP
+.P
A description of the
.B TIOCPKT
.BR ioctl (2),
which controls packet mode operation, can be found in
.BR ioctl_tty (2).
-.PP
+.P
The BSD
.BR ioctl (2)
operations