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Diffstat (limited to 'static/v10/man4/ttyld.4')
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diff --git a/static/v10/man4/ttyld.4 b/static/v10/man4/ttyld.4 new file mode 100644 index 00000000..b945a782 --- /dev/null +++ b/static/v10/man4/ttyld.4 @@ -0,0 +1,294 @@ +.TH TTYLD 4 +.CT 2 comm_term +.SH NAME +tty_ld \- terminal processing line discipline +.SH SYNOPSIS +.B #include <sys/ttyio.h> +.SH DESCRIPTION +.I Tty_ld +is usually inserted +into a stream +connected to a terminal device. +It gathers input into lines, +handles special characters like erase, kill, and interrupt, +inserts output delays, +and the like. +It does not deal with hardware parameters +such as speed and parity; +see +.IR tty (4) +for such matters. +.PP +Certain special characters have particular meaning on input. +These characters are not passed to a program +except in raw mode, where they lose their special character. +It is possible to change these characters from the default. +.PP +The +.I erase +character +(default +.BR # ) +erases the last-typed character. +It will not erase beyond the beginning of a line or +an end-of-file character. +.PP +The +.I kill +character +(default +.BR @ ) +erases the entire preceding part of the line, but not beyond +an end-of-file character. +.PP +The +.I end-of-file +character +(default +.RB control- d ) +causes any characters +waiting to be read +to be passed immediately +to the program, +without waiting for newline. +The +end-of-file character itself is discarded. +Thus if the end-of-file character +occurs at the beginning of a line, +there are no characters waiting, +and zero characters will be passed back; +this is +the standard end-of-file indication. +.PP +The +.I escape +character +.RB ( \e ) +escapes a following erase, kill, or end-of-file character +and allows it to be treated as ordinary data. +.PP +The +.I interrupt +character +(default +DEL) +is not passed to a program but sends +signal +.L SIGINT +to any processes in the process group of the stream; +see +.IR signal (2) +and +.IR stream (4). +.PP +The +.I quit +character +(default +FS, +.RB control- \e ) +sends signal +.BR SIGQUIT . +.PP +The +.I stop +character +(default DC3, +.RB control- s ) +delays printing on the terminal +until something is typed in. +.PP +The +.I start +character +(default DC1, +.RB control- q ) +restarts printing after +a stop character without generating +any input to a program. +.PP +Two +.IR ioctl (2) +calls affect these characters: +.TF TIOCGETC +.TP +.B TIOCGETC +The argument points to a +.B tchars +structure to be filled in with current settings. +.TP +.B TIOCSETC +The argument points to a +.B tchars +structure from which the characters are set. +.PD +.PP +The +.B tchars +structure, as defined in +.LR <sys/ttyio.h> , +is +.PP +.EX +.ta \w'struct 'u +\w'tchars 'u +\w't_startc; 'u +struct tchars { + char t_intrc; /* interrupt */ + char t_quitc; /* quit */ + char t_startc; /* start output */ + char t_stopc; /* stop output */ + char t_eofc; /* end-of-file */ + char t_brkc; /* input delimiter (like nl) */ +}; +.EE +.PP +A character value of 0377 +eliminates the effect of that character. +The +.L t_brkc +character, by default 0377, +acts like a new-line in that it terminates a line, +is echoed, and is passed to the program. +The stop and start characters may be the same, +to produce a toggle effect. +It is counterproductive to make +other special characters (including erase and kill) +identical. +.PP +Two +.I ioctl +calls affect other terminal processing parameters: +.TF TIOCGETP +.TP +.B TIOCGETP +The argument points to a +.B sgttyb +structure to be filled in with the current settings. +.TP +.B TIOCSETP +The argument points to a +.B sgttyb +structure from which the parameters are set. +.PD +.PP +The +.B sgttyb +structure, as +defined in +.LR <sys/ttyio.h> , +is +.EX +.ta \w'struct 'u +\w'sgttyb 'u +\w'sg_ispeed 'u +struct sgttyb { + char sg_ispeed; /* unused */ + char sg_ospeed; /* unused */ + char sg_erase; /* erase character */ + char sg_kill; /* kill character */ + short sg_flags; /* mode flags */ +}; +.EE +.PP +The flag bits are +.PP +.ta \w'\f5ALLDELAY\fP 'u +\w'\f50100000\fP 'u +.nf +\f5ALLDELAY 0177400\fP Delay algorithm selection +\f5VTDELAY 0040000\fP Form-feed and vertical-tab delays: +\f5FF0 0\fP +\f5FF1 0040000\fP +\f5CRDELAY 0030000\fP Carriage-return delays: +\f5CR0 0\fP +\f5CR1 0010000\fP +\f5CR2 0020000\fP +\f5CR3 0030000\fP +\f5TBDELAY 0006000\fP Tab delays: +\f5TAB0 0\fP +\f5TAB1 0002000\fP +\f5TAB2 0004000\fP +\f5XTABS 0006000\fP +\f5NLDELAY 0001400\fP New-line delays: +\f5NL0 0\fP +\f5NL1 0000400\fP +\f5NL2 0001000\fP +\f5NL3 0001400\fP +\f5RAW 0000040\fP Raw mode: wake up on all characters +\f5CRMOD 0000020\fP Map CR into LF; echo LF or CR as CR-LF +\f5ECHO 0000010\fP Echo (full duplex) +\f5LCASE 0000004\fP Map upper case to lower on input +\f5CBREAK 0000002\fP Return each character as soon as typed +\f5TANDEM 0000001\fP Automatic flow control +.DT +.fi +.PP +The delay bits specify how long +transmission stops to allow for mechanical or other movement +when certain characters are sent to the terminal. +In all cases a value of 0 indicates no delay. +.PP +If a form-feed/vertical tab delay is specified, +it lasts for about 2 seconds. +.PP +Carriage-return delay type 1 lasts about .08 seconds; +type 2 about .16 seconds; +type 3 about .32 seconds. +.PP +New-line delay type 1 is supposed to be for the Teletype model 37; +type 2 is about .10 seconds. +.PP +Tab delay type 1 is supposed to be for the Teletype model 37. +Type 3, called +.LR XTABS , +is not a delay at all but causes tabs to be replaced +by the appropriate number of spaces on output. +.PP +In +.B RAW +mode, +every character is passed immediately +to the program without waiting until a full line has been typed. +No erase or kill processing is done; +the end-of-file, interrupt, and quit characters +are not treated specially. +There are no delays and no echoing, and no replacement of +one character for another. +.PP +.L CRMOD +causes input carriage returns to be turned into +new-lines; +input of either CR or LF causes CR-LF both to +be echoed +(for terminals without a new-line function). +.PP +.L CBREAK +is a sort of half-cooked mode. +Programs read each character as soon as typed, instead +of waiting for a full line, +but quit and interrupt work, and output delays +.LR CRMOD , +.LR XTABS , +and +.LR ECHO +work normally. +On the other hand there is no erase or kill, +and no special treatment of +.L \e +or end-of-file. +.PP +.L TANDEM +mode causes the system to transmit +the stop character whenever the input +queue is in danger of overflowing, +and the start character +when the input queue has drained sufficiently. +It is useful for flow control when the `terminal' +is actually another machine that obeys the conventions. +.SH SEE ALSO +.IR getty (8), +.IR stty (1), +.IR signal (2), +.IR ioctl (2), +.IR stream (4), +.IR tty (4) +.SH BUGS +The +escape character +cannot be changed. |