- define values for termios
The following data types are defined through typedef:
used for terminal special characters
used for terminal baud rates
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:
size of the array c_cc for control characters
The following subscript names for the array c_cc are defined:
The subscript values are unique, except that the VMIN and VTIME subscripts can have the same values as the VEOF and VEOL subscripts, respectively.
The header file provides the flags described below.
The c_iflag field describes the basic terminal input control:
Signal interrupt on break.
Map CR to NL on input.
Ignore break condition.
Ignore characters with parity errors.
Map NL to CR on input.
Enable input parity check.
Enable any character to restart output.
Enable start/stop input control.
Enable start/stop output control.
Mark parity errors.
The c_oflag field specifies the system treatment of output:
Map NL to CR-NL on output.
Map CR to NL on output.
No CR output at column 0.
NL performs CR function.
Use fill characters for delay.
Select newline delays:
newline type 0
newline type 1
Select carriage-return delays:
carriage-return delay type 0
carriage-return delay type 1
carriage-return delay type 2
carriage-return delay type 3
Select horizontal-tab delays:
horizontal-tab delay type 0
horizontal-tab delay type 1
horizontal-tab delay type 2
expand tabs to spaces
Select backspace delays:
backspace-delay type 0
backspace-delay type 1
Select vertical-tab delays:
vertical-tab delay type 0
vertical-tab delay type 1
Select form-feed delays:
form-feed delay type 0
form-feed delay type 1
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.
1 200 baud
1 800 baud
2 400 baud
4 800 baud
9 600 baud
19 200 baud
38 400 baud
The c_cflag field describes the hardware control of the terminal; not all values specified are required to be supported by the underlying hardware:
Send two stop bits, else one.
Odd parity, else even.
Hang up on last close.
Ignore modem status lines.
The implementation supports the functionality associated with the symbols CS7, CS8, CSTOPB, PARODD, and PARENB.
The c_lflag field of the argument structure is used to control various terminal functions:
Echo erase character as error-correcting backspace.
Canonical input (erase and kill processing).
Enable extended input character processing.
Disable flush after interrupt or quit.
Send SIGTTOU for background output.
The following symbolic constants for use with tcsetattr() are defined:
Change attributes immediately.
Change attributes when output has drained.
Change attributes when output has drained; also flush pending input.
The following symbolic constants for use with tcflush() are defined:
Flush pending input.
Flush both pending input and untransmitted output.
Flush untransmitted output.
The following symbolic constants for use with tcflow() are defined:
Transmit a STOP character, intended to suspend input data.
Transmit a START character, intended to restart input data.
See attributes(5) for descriptions of the following attributes: