TERMIOS.H(3HEAD)TERMIOS.H(3HEAD)NAME
termios.h, termios - define values for termiosSYNOPSIS
#include <termios.h>
DESCRIPTION
The <termios.h> header contains the definitions used by the terminal
I/O interfaces. See termios(3C) and termio(7I) for an overview of the
terminal interface.
The termios Structure
The following data types are defined through typedef:
cc_t
used for terminal special characters
speed_t
used for terminal baud rates
tcflag_t
used for terminal modes
The above types are all unsigned integer types.
The implementation supports one or more programming environments in
which the widths of cc_t, speed_t, and tcflag_t are no greater than the
width of type long. The names of these programming environments can be
obtained using the confstr(3C) function or the getconf(1) utility.
The termios structure is defined and includes the following members:
tcflag_t c_iflag /* input modes */
tcflag_t c_oflag /* output modes */
tcflag_t c_cflag /* control modes */
tcflag_t c_lflag /* local modes */
cc_t c_cc[NCCS] /* control characters */
A definition is provided for:
NCCS
size of the array c_cc for control characters
The following subscript names for the array c_cc are defined:
Subscript UsageCanonical Mode Subscript UsageNon-Canonical Mode Description
─────────────────────────────────────────────────────────────────────────────────────
VEOF EOF character
VEOL EOL character
VERASE ERASE character
VINTR VINTR INTR character
VKILL KILL character
VMIN MIN value
VQUIT VQUIT QUIT character
VSTART VSTART START character
VSTOP VSTOP STOP character
VSUSP VSUSP SUSP character
VTIME TIME value
VSTATUS STATUS character
The subscript values are unique, except that the VMIN and VTIME sub‐
scripts can have the same values as the VEOF and VEOL subscripts,
respectively.
The header file provides the flags described below.
Input Modes
The c_iflag field describes the basic terminal input control:
BRKINT
Signal interrupt on break.
ICRNL
Map CR to NL on input.
IGNBRK
Ignore break condition.
IGNCR
Ignore CR.
IGNPAR
Ignore characters with parity errors.
INLCR
Map NL to CR on input.
INPCK
Enable input parity check.
ISTRIP
Strip character.
IXANY
Enable any character to restart output.
IXOFF
Enable start/stop input control.
IXON
Enable start/stop output control.
PARMRK
Mark parity errors.
Output Modes
The c_oflag field specifies the system treatment of output:
OPOST
Post-process output.
ONLCR
Map NL to CR-NL on output.
OCRNL
Map CR to NL on output.
ONOCR
No CR output at column 0.
ONLRET
NL performs CR function.
OFILL
Use fill characters for delay.
NLDLY
Select newline delays:
NL0
newline type 0
NL1
newline type 1
CRDLY
Select carriage-return delays:
CR0
carriage-return delay type 0
CR1
carriage-return delay type 1
CR2
carriage-return delay type 2
CR3
carriage-return delay type 3
TABDLY
Select horizontal-tab delays:
TAB0
horizontal-tab delay type 0
TAB1
horizontal-tab delay type 1
TAB2
horizontal-tab delay type 2
TAB3
expand tabs to spaces
BSDLY
Select backspace delays:
BS0
backspace-delay type 0
BS1
backspace-delay type 1
VTDLY
Select vertical-tab delays:
VT0
vertical-tab delay type 0
VT1
vertical-tab delay type 1
FFDLY
Select form-feed delays:
FF0
form-feed delay type 0
FF1
form-feed delay type 1
Baud Rate Selection
The input and output baud rates are stored in the termios structure.
These are the valid values for objects of type speed_ t. The following
values are defined, but not all baud rates need be supported by the
underlying hardware.
B0
Hang up
B50
50 baud
B75
75 baud
B110
110 baud
B134
134.5 baud
B150
150 baud
B200
200 baud
B300
300 baud
B600
600 baud
B1200
1 200 baud
B1800
1 800 baud
B2400
2 400 baud
B4800
4 800 baud
B9600
9 600 baud
B19200
19 200 baud
B38400
38 400 baud
Control Modes
The c_cflag field describes the hardware control of the terminal; not
all values specified are required to be supported by the underlying
hardware:
CSIZE
Character size:
CS5
5 bits
CS6
6 bits
CS7
7 bits
CS8
8 bits
CSTOPB
Send two stop bits, else one.
CREAD
Enable receiver.
PARENB
Parity enable.
PARODD
Odd parity, else even.
HUPCL
Hang up on last close.
CLOCAL
Ignore modem status lines.
The implementation supports the functionality associated with the sym‐
bols CS7, CS8, CSTOPB, PARODD, and PARENB.
Local Modes
The c_lflag field of the argument structure is used to control various
terminal functions:
ECHO
Enable echo.
ECHOE
Echo erase character as error-correcting backspace.
ECHOK
Echo KILL.
ECHONL
Echo NL.
ICANON
Canonical input (erase and kill processing).
IEXTEN
Enable extended input character processing.
ISIG
Enable signals.
NOFLSH
Disable flush after interrupt or quit.
TOSTOP
Send SIGTTOU for background output.
Attribute Selection
The following symbolic constants for use with tcsetattr() are defined:
TCSANOW
Change attributes immediately.
TCSADRAIN
Change attributes when output has drained.
TCSAFLUSH
Change attributes when output has drained; also flush
pending input.
Line Control
The following symbolic constants for use with tcflush() are defined:
TCIFLUSH
Flush pending input.
TCIOFLUSH
Flush both pending input and untransmitted output.
TCOFLUSH
Flush untransmitted output.
The following symbolic constants for use with tcflow() are defined:
TCIOFF
Transmit a STOP character, intended to suspend input data.
TCION
Transmit a START character, intended to restart input data.
TCOOFF
Suspend output.
TCOON
Restart output.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬─────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼─────────────────┤
│Interface Stability │ Standard │
└────────────────────┴─────────────────┘
SEE ALSOgetconf(1), cfgetispeed(3C), cfsetispeed(3C), confstr(3C), tcdrain(3C),
tcflow(3C), tcflush(3C), tcgetattr(3C), tcgetsid(3C), tcsendbreak(3C),
tcsetattr(3C), attributes(5), standards(5)
Jan 04, 2014 TERMIOS.H(3HEAD)