stty —
set options for a terminal device interface
  
    | stty | [ -a|-e|-g] [-ffile] [operand ...] | 
The stty utility sets or reports on terminal
  characteristics for the device that is its standard input. If no options or
  operands are specified, it reports the settings of a subset of characteristics
  as well as additional ones if they differ from their default values. Otherwise
  it modifies the terminal state according to the specified arguments. Some
  combinations of arguments are mutually exclusive on some terminal types.
The following options are available:
  - -a
- Display all the current settings for the terminal to standard output as
      per IEEE Std 1003.2
    (“POSIX.2”).
- -e
- Display all the current settings for the terminal to standard output in
      the traditional BSD “all” and
      “everything” formats.
- -ffile
- Open and use the terminal named by file rather than
      using standard input. The file is opened using the
      O_NONBLOCKflag ofopen(),
      making it possible to set or display settings on a terminal that might
      otherwise block on the open.
- -g
- Display all the current settings for the terminal to standard output in a
      form that may be used as an argument to a subsequent invocation of
      sttyto restore the current terminal state as per
      IEEE Std 1003.2 (“POSIX.2”).
The following arguments are available to set the terminal
    characteristics:
Control mode flags affect hardware characteristics associated with the terminal.
  This corresponds to the c_cflag of the
  termios(4) structure.
  - parenb(- -parenb)
- Enable (disable) parity generation and detection.
- parodd(- -parodd)
- Select odd (even) parity.
- cs5
    cs6 cs7 cs8
- Select character size, if possible.
- number
- Set terminal baud rate to number, if possible. If
      the baud rate is set to zero, modem control is no longer asserted.
- ispeednumber
- Set terminal input baud rate to number, if possible.
      If the input baud rate is set to zero, the input baud rate is set to the
      value of the output baud rate.
- ospeednumber
- Set terminal output baud rate to number, if
      possible. If the output baud rate is set to zero, modem control is no
      longer asserted.
- speednumber
- This sets both ispeedandospeedto number.
- hupcl(- -hupcl)
- Stop asserting modem control (do not stop asserting modem control) on last
      close.
- hup(- -hup)
- Same as hupcl (-hupcl).
- cstopb(- -cstopb)
- Use two (one) stop bits per character.
- cread(- -cread)
- Enable (disable) the receiver.
- clocal(- -clocal)
- Assume a line without (with) modem control.
- crtscts(- -crtscts)
- Enable RTS/CTS flow control.
- cdtrcts(- -cdtrcts)
- Enable DTR/CTS flow control (if supported).
This corresponds to the c_iflag of the
  termios(4) structure.
  - ignbrk(- -ignbrk)
- Ignore (do not ignore) break on input.
- brkint(- -brkint)
- Signal (do not signal) INTRon break.
- ignpar(- -ignpar)
- Ignore (do not ignore) parity errors.
- parmrk(- -parmrk)
- Mark (do not mark) parity errors.
- inpck(- -inpck)
- Enable (disable) input parity checking.
- istrip(- -istrip)
- Strip (do not strip) input characters to seven bits.
- inlcr(- -inlcr)
- Map (do not map) NLtoCRon input.
- igncr(- -igncr)
- Ignore (do not ignore) CRon input.
- icrnl(- -icrnl)
- Map (do not map) CRtoNLon input.
- ixon(- -ixon)
- Enable (disable) START/STOPoutput control. Output
      from the system is stopped when the system receivesSTOPand started when the system receivesSTART, or ifixanyis set,
      any character restarts output.
- ixoff(- -ixoff)
- Request that the system send (not send) START/STOPcharacters when the input queue is nearly empty/full.
- ixany(- -ixany)
- Allow any character (allow only START) to restart
      output.
- imaxbel(- -imaxbel)
- The system imposes a limit of MAX_INPUT(currently
      255) characters in the input queue. Ifimaxbelis
      set and the input queue limit has been reached, subsequent input causes
      the system to send an ASCII BEL character to the output queue (the
      terminal beeps at you). Otherwise, ifimaxbelis
      unset and the input queue is full, the next input character causes the
      entire input and output queues to be discarded.
This corresponds to the c_oflag of the
  termios(4) structure.
  - opost(- -opost)
- Post-process output (do not post-process output; ignore all other output
      modes).
- onlcr(- -onlcr)
- Map (do not map) NLtoCR-NLon output.
- ocrnl(- -ocrnl)
- Map (do not map) CRtoNLon output.
- oxtabs(- -oxtabs)
- Expand (do not expand) tabs to spaces 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.
Local mode flags (lflags) affect various and sundry characteristics of terminal
  processing. Historically the term "local" pertained to new job
  control features implemented by Jim Kulp on a PDP-11/70 at IIASA. Later the
  driver ran on the first VAX at Evans Hall, UC Berkeley, where the job control
  details were greatly modified but the structure definitions and names remained
  essentially unchanged. The second interpretation of the ‘l’ in
  lflag is “line discipline flag”, which corresponds to the
  c_lflag of the
  termios(4) structure.
  - isig(- -isig)
- Enable (disable) the checking of characters against the special control
      characters INTR,QUIT, andSUSP.
- icanon(- -icanon)
- Enable (disable) canonical input (ERASEandKILLprocessing).
- iexten(- -iexten)
- Enable (disable) any implementation defined special control characters not
      currently controlled by icanon, isig, or ixon.
- echo(- -echo)
- Echo back (do not echo back) every character typed.
- echoe(- -echoe)
- The ERASEcharacter shall (shall not) visually
      erase the last character in the current line from the display, if
      possible.
- echok(- -echok)
- Echo (do not echo) NLafterKILLcharacter.
- echoke(- -echoke)
- The KILLcharacter shall (shall not) visually
      erase the current line from the display, if possible.
- echonl(- -echonl)
- Echo (do not echo) NL, even if echo is
    disabled.
- echoctl(- -echoctl)
- If echoctlis set, echo control characters as ^X.
      Otherwise control characters echo as themselves.
- echoprt(- -echoprt)
- For printing terminals. If set, echo erased characters backwards within
      “\” and “/”. Otherwise, disable this
    feature.
- noflsh(- -noflsh)
- Disable (enable) flush after INTR,QUIT,SUSP.
- tostop(- -tostop)
- Send (do not send) SIGTTOUfor background output.
      This causes background jobs to stop if they attempt terminal output.
- altwerase(- -altwerase)
- Use (do not use) an alternative word erase algorithm when processing
      WERASEcharacters. This alternative algorithm
      considers sequences of alphanumeric/underscores as words. It also skips
      the first preceding character in its classification (as a convenience
      since the one preceding character could have been erased with simply anERASEcharacter).
- mdmbuf(- -mdmbuf)
- If set, flow control output based on condition of Carrier Detect.
      Otherwise writes return an error if Carrier Detect is low (and Carrier is
      not being ignored with the CLOCALflag).
- flusho(- -flusho)
- Indicates output is (is not) being discarded.
- pendin(- -pendin)
- Indicates input is (is not) pending after a switch from non-canonical to
      canonical mode and will be re-input when a read becomes pending or more
      input arrives.
  - control-character string
- Set control-character to string
      string. If the string is a single character, then
      the control character is set to that character. If the string is the two
      character sequence "^-" or the string "undef", then
      the control character is disabled (i.e., set to
      {_POSIX_VDISABLE}).Recognized control characters: 
    
      
        | control- |  |  |  
        | character | Subscript | Description |  
        | _________ | _________ | _______________ |  
        | eof | VEOF | EOF character |  
        | eol | VEOL | EOL character |  
        | eol2 | VEOL2 | EOL2 character |  
        | erase | VERASE | ERASE character |  
        | werase | VWERASE | WERASE character |  
        | kill | VKILL | KILL character |  
        | reprint | VREPRINT | REPRINT character |  
        | intr | VINTR | INTR character |  
        | quit | VQUIT | QUIT character |  
        | susp | VSUSP | SUSP character |  
        | dsusp | VDSUSP | DSUSP character |  
        | start | VSTART | START character |  
        | stop | VSTOP | STOP character |  
        | lnext | VLNEXT | LNEXT character |  
        | status | VSTATUS | STATUS character |  
        | discard | VDISCARD | DISCARD character |  
 
 
- minnumber
-  
- timenumber
- Set the value of min or time to number.
      MINandTIMEare used in
      Non-Canonical mode input processing (-icanon).
  - saved settings
- Set the current terminal characteristics to the saved settings produced by
      the -goption.
- evenpor- parity
- Enable parenb and cs7; disable parodd.
- oddp
- Enable parenb, cs7, and parodd.
- -parity,- -evenp,- -oddp
- Disable parenb, and set cs8.
- nl(- -nl)
- Enable (disable) icrnl. In addition -nl unsets inlcr and igncr.
- ek
- Reset ERASEandKILLcharacters back to system defaults.
- sane
- Resets all modes to reasonable values for interactive terminal use.
- insane
- Sets all modes to random values, which are very likely (but not
      guaranteed) to be unreasonable for interactive terminal use.
- tty
- Set the line discipline to the standard terminal line discipline
      TTYDISC.
- crt(- -crt)
- Set (disable) all modes suitable for a CRT display device.
- kerninfo(- -kerninfo)
- Enable (disable) the system generated status line associated with
      processing a STATUScharacter (usually set to ^T).
      The status line consists of the system load average, the current command
      name, its process ID, the event the process is waiting on (or the status
      of the process), the user and system times, percent CPU, and current
      memory usage.
- colsnumber
- The terminal size is recorded as having number
      columns.
- columnsnumber
- An alias for cols.
- rowsnumber
- The terminal size is recorded as having number
    rows.
- dec
- Set modes suitable for users of Digital Equipment Corporation systems
      (ERASE,KILL, andINTRcharacters are set to ^?, ^U, and ^C;ixanyis disabled, andcrtis enabled).
- extproc(- -extproc)
- If set, this flag indicates that some amount of terminal processing is
      being performed by either the terminal hardware or by the remote side
      connected to a pty.
- raw(- -raw)
- If set, change the modes of the terminal so that no input or output
      processing is performed. If unset, change the modes of the terminal to
      some reasonable state that performs input and output processing. Note that
      since the terminal driver no longer has a single
      RAWbit, it is not possible to intuit what flags
      were set prior to settingraw. This means that
      unsettingrawmay not put back all the setting
      that were previously in effect. To set the terminal into a raw state and
      then accurately restore it, the following shell code is recommended:
    
save_state=$(stty -g)
stty raw
...
stty "$save_state"
    
 
- size
- The size of the terminal is printed as two numbers on a single line, first
      rows, then columns.
These modes remain for compatibility with the previous version of thestty utility.
  - all
- Reports all the terminal modes as with stty-aexcept that the control characters are printed
      in a columnar format.
- everything
- Same as all.
- cooked
- Same as sane.
- cbreak
- If set, enables brkint,ixon,imaxbel,opost,isig,iexten, and-icanon. If
      unset, same assane.
- new
- Same as tty.
- old
- Same as tty.
- newcrt(- -newcrt)
- Same as crt.
- pass8
- The converse of parity.
- tandem(- -tandem)
- Same as ixoff.
- decctlq(- -decctlq)
- The converse of ixany.
- crterase(- -crterase)
- Same as echoe.
- crtbs(- -crtbs)
- Same as echoe.
- crtkill(- -crtkill)
- Same as echoke.
- ctlecho(- -ctlecho)
- Same as echoctl.
- prterase(- -prterase)
- Same as echoprt.
- litout(- -litout)
- The converse of opost.
- tabs(- -tabs)
- The converse of oxtabs.
- brkvalue
- Same as the control character eol.
- flushvalue
- Same as the control character discard.
- rprntvalue
- Same as the control character reprint.
These operations are not modes, but rather commands to be performed by the tty
  layer.
  - ostart
- Performs a "start output" operation, as normally done by an
      incoming START character when ixonis set.
- ostop
- Performs a "stop output" operation, as normally done by an
      incoming STOP character when ixonis set.
Thestty utility exits 0 on success,
  and >0 if an error occurs.
The stty utility is expected to be IEEE
  Std 1003.2 (“POSIX.2”) compatible. The
  -e and -f flags are extensions
  to the standard, as are the operands mentioned in the control operations
  section.
An stty utility appeared in
  Version 2 AT&T UNIX.