The array c_cc specifies the special control-characters that affect the operation of the communication-port and the processing of terminal input and output as described in the ``Special characters'' section below. For each entry of the control-character array c_cc, the following are typical default values:
Terminal device control character array
|Subscript value||Subscript name||Character value||Character description|
|0||VINTR||ASCII DEL||INTR character|
|1||VNUIT||ASCII FS||QUIT character|
|4||VEOF||ASCII EOT||EOF character|
|5||VEOL||ASCII NUL||EOL character|
|8||VSTART||ASCII DC1||START character|
|9||VSTOP||ASCII DC3||STOP character|
|10||VSUSP||ASCII SUB||SUSP character|
The subscript values are unique, except that the VMIN and VTIME subscripts may have the same value as the VEOF and VEOL subscripts respectively. The <termios.h> header file defines the relative positions, subscript names and default values for the control-character array c_cc (see ``Special control characters'' in termio(7)).
The NL and CR character cannot be changed. The INTR, QUIT, ERASE, KILL, EOF, EOL, SUSP, STOP and START characters can be changed as follows:
struct termios term; term.c_cc[VINTR] = `a'; term.c_cc[VQUIT] = `b'; term.c_cc[VERASE] = `c'; term.c_cc[VKILL] = `d'; term.c_cc[VEOF] = `e'; term.c_cc[VEOL] = `f'; term.c_cc[VSUSP] = `g'; term.c_cc[VSTOP] = `h'; term.c_cc[VSTART] = `i';
where a, b, c, d, e, f, g, h and i are the INTR, QUIT, ERASE, KILL, EOF, EOL, SUSP, STOP and START characters respectively.
Implementations which prohibit changing the START and STOP characters may ignore the character values in the c_cc array indexed by the VSTART and VSTOP subscripts when tcsetattr is called, but return the character value when tcsetattr is called (see tcsetattr in termios(3C)).
If _POSIX_VDISABLE is defined for the terminal-device-file, and the value of one of the changeable special control-characters equals _POSIX_VDISABLE, that function is disabled; that is, the special character is ignored on input and is not recognized (see ``Special characters'' section below). If ICANON is clear, the value of _POSIX_VDISABLE lacks any special meaning for the VMIN and VTIME entries of the c_cc array.