Tribblix: manual page: stty.1

STTY(1) User Commands STTY(1)

NAME

stty - set the options for a terminal

SYNOPSIS

/usr/bin/stty [-a] [-g]

/usr/bin/stty [modes]

/usr/xpg4/bin/stty [-a | -g]

/usr/xpg4/bin/stty [modes]

/usr/xpg6/bin/stty [-a | -g]

/usr/xpg6/bin/stty [modes]

DESCRIPTION

The stty utility sets certain terminal I/O options for the device
that is the current standard input. Without arguments, stty reports
the settings of certain options.

In this report, if a character is preceded by a caret (^), then the
value of that option is the corresponding control character (for
example, ^h is CTRL-h. In this case, recall that CTRL-h is the same
as the BACKSPACE key). The sequence ^@ means that an option has a
null value.

See termio(4I) for detailed information about the modes listed from
Control Modes through Local Modes. For detailed information about the
modes listed under Hardware Flow Control Modes and Clock Modes, see
termiox(4I).

Operands described in the Combination Modes section are implemented
using options in the earlier sections. Notice that many combinations
of options make no sense, but no sanity checking is performed.
Hardware flow control and clock modes options might not be supported
by all hardware interfaces.

OPTIONS

The following options are supported:

-a
Writes to standard output all of the option settings for the
terminal.

-g
Reports current settings in a form that can be used as an
argument to another stty command. Emits termios-type output if
the underlying driver supports it. Otherwise, it emits termio-
type output.

OPERANDS

The following mode operands are supported:

Control Modes

parenb(-parenb)
Enable (disable) parity generation and
detection.

parext(-parext)
Enable (disable) extended parity generation
and detection for mark and space parity.

parodd(-parodd)
Select odd (even) parity, or mark (space)
parity if parext is enabled.

cs5 cs6 cs7 cs8
Select character size (see termio(4I)).

0
Hang up line immediately.

hupcl (-hupcl)
Hang up (do not hang up) connection on last
close.

hup (-hup)
Same as hupcl(-hupcl).

cstopb (-cstopb)
Use two (one) stop bits per character.

cread (-cread)
Enable (disable) the receiver.

crtscts (-crtscts)
Enable output hardware flow control. Raise
the RTS (Request to Send) modem control line.
Suspends output until the CTS (Clear to Send)
line is raised.

crtsxoff (-crtsxoff)
Enable input hardware flow control. Raise the
RTS (Request to Send) modem control line to
receive data. Suspends input when RTS is low.

clocal (-clocal)
Assume a line without (with) modem control.

defeucw
Set the widths of multibyte characters to the
values defined in the current locale
specified by LC_CTYPE. Internally, width is
expressed in terms of bytes per character,
and screen or display columns per character.

110 300 600 1200 1800
2400 4800 9600 19200
38400 357600 76800 115200
153600 230400 307200 460800
921600 1000000 1152000 1500000
2000000 2500000 3000000 3500000
4000000

Set terminal baud rate to the number given, if possible. (All
speeds are not supported by all hardware interfaces.)

ispeed 0 110 300 600 1200
1800 2400 4800 9600 19200
38400 57600 76800 115200
153600 230400 307200 460800
921600 1000000 1152000 1500000
2000000 2500000 3000000 3500000
4000000

Set terminal input baud rate to the number given, if possible.
(Not all hardware supports split baud rates.) If the input baud
rate is set to 0, the input baud rate is specified by the value
of the output baud rate.

ospeed 0 110 300 600 1200
1800 2400 4800 9600 19200
38400 57600 76800 115200
153600 230400 307200 460800
921600 1000000 1152000 1500000
2000000 2500000 3000000 3500000
4000000

Set terminal output baud rate to the number given, if possible.
(Not all hardware supports split baud rates.) If the output baud
rate is set to 0, the line is hung up immediately.

Input Modes

ignbrk (-ignbrk)
Ignore (do not ignore) break on input.

brkint (-brkint)
Signal (do not signal) INTR on break.

ignpar (-ignpar)
Ignore (do not ignore) parity errors.

parmrk (-parmrk)
Mark (do not mark) parity errors (see
termio(4I)).

inpck (-inpck)
Enable (disable) input parity checking.

istrip (-istrip)
Strip (do not strip) input characters to seven
bits.

inlcr (-inlcr)
Map (do not map) NL to CR on input.

igncr (-igncr)
Ignore (do not ignore) CR on input.

icrnl (-icrnl)
Map (do not map) CR to NL on input.

iuclc (-iuclc)
Map (do not map) upper-case alphabetics to
lower case on input.

ixon (-ixon)
Enable (disable) START/STOP output control.
Output is stopped by sending STOP control
character and started by sending the START
control character.

ixany (-ixany)
Allow any character (only DC1) to restart
output.

ixoff (-ixoff)
Request that the system send (not send)
START/STOP characters when the input queue is
nearly empty/full.

imaxbel (-imaxbel)
Echo (do not echo) BEL when the input line is
too long. If imaxbel is set, the ASCII BEL
character (07 hex) is echoed if the input
stream overflows. Further input is not stored,
but any input already present is not disturbed.
If -imaxbel is set, no BEL character is echoed,
and all unread input present in the input queue
is discarded if the input stream overflows.

Output Modes

opost (-opost)
Post-process output (do not post-process
output; ignore all other output modes).

olcuc (-olcuc)
Map (do not map) lower-case alphabetics to
upper case on output.

onlcr (-onlcr)
Map (do not map) NL to CR-NL on output.

ocrnl (-ocrnl)
Map (do not map) CR to NL on output.

onocr (-onocr)
Do not (do) output CRs at column zero.

onlret (-onlret)
On the terminal NL performs (does not perform)
the CR function.

ofill (-ofill)
Use fill characters (use timing) for delays.

ofdel (-ofdel)
Fill characters are DELs (NULs).

cr0 cr1 cr2 cr3
Select style of delay for carriage returns
(see termio(4I)).

nl0 nl1
Select style of delay for line-feeds (see
termio(4I)).

tab0 tab1 tab2 tab3
Select style of delay for horizontal tabs (see
termio(4I)).

bs0 bs1
Select style of delay for backspaces (see
termio(4I)).

ff0 ff1
Select style of delay for form-feeds (see
termio(4I)).

vt0 vt1
Select style of delay for vertical tabs (see
termio(4I)).

Local Modes

isig(-isig)
Enable (disable) the checking of characters
against the special control characters INTR,
QUIT, SWTCH, and SUSP. For information on
SWTCH, see NOTES.

icanon (-icanon)
Enable (disable) canonical input (ERASE and
KILL processing). Does not set MIN or TIME.

xcase (-xcase)
Canonical (unprocessed) upper/lower-case
presentation.

echo (-echo)
Echo back (do not echo back) every character
typed.

echoe (-echoe)
Echo (do not echo) ERASE character as a
backspace-space-backspace string. This mode
erases the ERASEed character on many CRT
terminals; however, it does not keep track of
column position and, as a result, it might be
confusing for escaped characters, tabs, and
backspaces.

echok(-echok)
Echo (do not echo) NL after KILL character.

lfkc (-lfkc)
The same as echok(-echok); obsolete.

echonl (-echonl)
Echo (do not echo) NL.

noflsh (-noflsh)
Disable (enable) flush after INTR, QUIT, or
SUSP.

stwrap (-stwrap)
Disable (enable) truncation of lines longer
than 79 characters on a synchronous line.

tostop (-tostop)
Send (do not send) SIGTTOU when background
processes write to the terminal.

echoctl (-echoctl)
Echo (do not echo) control characters as ^char,
delete as ^?.

echoprt (-echoprt)
Echo (do not echo) erase character as character
is ``erased''.

echoke (-echoke)
BS-SP-BS erase (do not BS-SP-BS erase) entire
line on line kill.

flusho (-flusho)
Output is (is not) being flushed.

pendin (-pendin)
Retype (do not retype) pending input at next
read or input character.

iexten (-iexten)
Enable (disable) special control characters not
currently controlled by icanon, isig, ixon, or
ixoff: VEOL, VSWTCH, VREPRINT, VDISCARD,
VDSUSP, VWERASE, and VLNEXT.

stflush (-stflush)
Enable (disable) flush on a synchronous line
after every write(2).

stappl (-stappl)
Use application mode (use line mode) on a
synchronous line.

Hardware Flow Control Modes

rtsxoff (-rtsxoff)
Enable (disable) RTS hardware flow control on
input.

ctsxon (-ctsxon)
Enable (disable) CTS hardware flow control on
output.

dtrxoff (-dtrxoff)
Enable (disable) DTR hardware flow control on
input.

cdxon (-cdxon)
Enable (disable) CD hardware flow control on
output.

isxoff (-isxoff)
Enable (disable) isochronous hardware flow
control on input.

Clock Modes

xcibrg
Get transmit clock from internal baud rate generator.

xctset
Get the transmit clock from transmitter signal element
timing (DCE source) lead, CCITT V.24 circuit 114,
EIA-232-D pin 15.

xcrset
Get transmit clock from receiver signal element timing
(DCE source) lead, CCITT V.24 circuit 115, EIA-232-D pin
17.

rcibrg
Get receive clock from internal baud rate generator.

rctset
Get receive clock from transmitter signal element timing
(DCE source) lead, CCITT V.24 circuit 114, EIA-232-D pin
15.

rcrset
Get receive clock from receiver signal element timing
(DCE source) lead, CCITT V.24 circuit 115, EIA-232-D pin
17.

tsetcoff
Transmitter signal element timing clock not provided.

tsetcrbrg
Output receive baud rate generator on transmitter signal
element timing (DTE source) lead, CCITT V.24 circuit
113, EIA-232-D pin 24.

tsetctbrg
Output transmit baud rate generator on transmitter
signal element timing (DTE source) lead, CCITT V.24
circuit 113, EIA-232-D pin 24.

tsetctset
Output transmitter signal element timing (DCE source) on
transmitter signal element timing (DTE source) lead,
CCITT V.24 circuit 113, EIA-232-D pin 24.

tsetcrset
Output receiver signal element timing (DCE source) on
transmitter signal element timing (DTE source) lead,
CCITT V.24 circuit 113, EIA-232-D pin 24.

rsetcoff
Receiver signal element timing clock not provided.

rsetcrbrg
Output receive baud rate generator on receiver signal
element timing (DTE source) lead, CCITT V.24 circuit
128, no EIA-232-D pin.

rsetctbrg
Output transmit baud rate generator on receiver signal
element timing (DTE source) lead, CCITT V.24 circuit
128, no EIA-232-D pin.

rsetctset
Output transmitter signal element timing (DCE source) on
receiver signal element timing (DTE source) lead, CCITT
V.24 circuit 128, no EIA-232-D pin.

rsetcrset
Output receiver signal element timing (DCE source) on
receiver signal element timing (DTE source) lead, CCITT
V.24 circuit 128, no EIA-232-D pin.

Control Assignments

control-character c

Set control-character to c, where:

control-character
is ctab, discard, dsusp, eof, eol, eol2,
erase, erase2, intr, kill, lnext, quit,
reprint, start, stop, susp, status, swtch,
or werase (ctab is used with -stappl, see
termio(4I)). For information on swtch, see
NOTES.

c
If c is a single character, the control
character is set to that character.

In the POSIX locale, if c is preceded by a
caret (^) indicating an escape from the
shell and is one of those listed in the ^c
column of the following table, then its
value used (in the Value column) is the
corresponding control character (for
example, ``^d'' is a CTRL-d). ``^?'' is
interpreted as DEL and ``^-'' is interpreted
as undefined.

+-------------------------------------------+
| ^c Value ^c Value ^c Value |
|a, A <SOH> l, L <FF> w, W <ETB> |
|b, B <STX> m, M <CR> x, X <CAN> |
|c, C <ETX> n, N <SO> y, Y <EM> |
|d, D <EOT> o, O <SI> z, Z <SUB> |
|e, E <ENQ> p, P <DLE> [ <ESC> |
|f, F <ACK> q, Q <DC1> \ <FS> |
|g, G <BEL> r, R <DC2> ] <GS> |
|h, H <BS> s, S <DC3> ^ <RS> |
|i, I <HT> t, T <DC4> _ <US> |
|j, J <LF> u, U <NAK> ? <DEL> |
|k, K <VT> v, V <SYN> |
+-------------------------------------------+

min number
time number
Set the value of min or time to number. MIN and TIME
are used in Non-Canonical mode input processing
(-icanon).

line i
Set line discipline to i ( 0< i <127).

Combination Modes

saved settings
Set the current terminal characteristics to
the saved settings produced by the -g option.

evenp or parity
Enable parenb and cs7, or disable parodd.

oddp
Enable parenb, cs7, and parodd.

spacep
Enable parenb, cs7, and parext.

markp
Enable parenb, cs7, parodd, and parext.

-parity, or -evenp
Disable parenb, and set cs8.

-oddp
Disable parenb and parodd, and set cs8.

-spacep
Disable parenb and parext, and set cs8.

-markp
Disable parenb, parodd, and parext, and set
cs8.

raw (-raw or cooked)
Enable (disable) raw input and output. Raw
mode is equivalent to setting:

stty cs8 -icanon min 1 time 0 -isig -xcase \
-inpck -opost

/usr/bin/stty, /usr/xpg6/bin/stty
nl (-nl)
Unset (set) icrnl, onlcr. In addition -nl unsets inlcr,
igncr, ocrnl, and onlret.

/usr/xpg4/bin/stty
nl (-nl)
Set (unset) icrnl. In addition, -nl unsets
inlcr, igncr, ocrnl, and onlret; -nl sets
onlcr, and nl unsets onlcr.

lcase (-lcase)
Set (unset) xcase, iuclc, and olcuc.

LCASE (-LCASE)
Same as lcase (-lcase).

tabs (-tabs or tab3)
Preserve (expand to spaces) tabs when
printing.

ek
Reset ERASE, ERASE2, and KILL characters back
to normal DEL, CTRL-h, and CTRL-u,
respectively.

sane
Reset all modes to some reasonable values.

term
Set all modes suitable for the terminal type
term, where term is one of tty33, tty37,
vt05, tn300, ti700, or tek.

async
Set normal asynchronous communications where
clock settings are xcibrg, rcibrg, tsetcoff
and rsetcoff.

Window Size

rows n
Set window size to n rows.

columns n
Set window size to n columns.

cols n
Set window size to n columns. cols is a shorthand alias
for columns.

ypixels n
Set vertical window size to n pixels.

xpixels n
Set horizontal window size to n pixels.

USAGE

The -g flag is designed to facilitate the saving and restoring of
terminal state from the shell level. For example, a program can:

saveterm="$(stty -g)" # save terminal state
stty (new settings) # set new state
... # ...
stty $saveterm # restore terminal state

Since the -a format is so loosely specified, scripts that save and
restore terminal settings should use the -g option.

ENVIRONMENT VARIABLES

See environ(7) for descriptions of the following environment
variables that affect the execution of stty: LANG, LC_ALL, LC_CTYPE,
LC_MESSAGES, and NLSPATH.

EXIT STATUS

The following exit values are returned:

0
Successful completion.

>0
An error occurred.

ATTRIBUTES

NOTES

Solaris does not support any of the actions implied by swtch, which
was used by the sxt driver on System V release 4. Solaris allows the
swtch value to be set, and prints it out if set, but it does not
perform the swtch action.

The job switch functionality on Solaris is actually handled by job
control. susp is the correct setting for this.

August 13, 2021 STTY(1)