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diff --git a/man3/termios.3 b/man3/termios.3 deleted file mode 100644 index 28a5411..0000000 --- a/man3/termios.3 +++ /dev/null @@ -1,1235 +0,0 @@ -'\" t -.\" Copyright (c) 1993 Michael Haardt (michael@moria.de) -.\" Fri Apr 2 11:32:09 MET DST 1993 -.\" Copyright (c) 2006-2015, Michael Kerrisk <mtk.manpages@gmail.com> -.\" -.\" SPDX-License-Identifier: GPL-2.0-or-later -.\" -.\" Modified 1993-07-24 by Rik Faith <faith@cs.unc.edu> -.\" Modified 1995-02-25 by Jim Van Zandt <jrv@vanzandt.mv.com> -.\" Modified 1995-09-02 by Jim Van Zandt <jrv@vanzandt.mv.com> -.\" moved to man3, aeb, 950919 -.\" Modified 2001-09-22 by Michael Kerrisk <mtk.manpages@gmail.com> -.\" Modified 2001-12-17, aeb -.\" Modified 2004-10-31, aeb -.\" 2006-12-28, mtk: -.\" Added .SS headers to give some structure to this page; and a -.\" small amount of reordering. -.\" Added a section on canonical and noncanonical mode. -.\" Enhanced the discussion of "raw" mode for cfmakeraw(). -.\" Document CMSPAR. -.\" -.TH termios 3 2023-10-31 "Linux man-pages 6.7" -.SH NAME -termios, tcgetattr, tcsetattr, tcsendbreak, tcdrain, tcflush, tcflow, -cfmakeraw, cfgetospeed, cfgetispeed, cfsetispeed, cfsetospeed, cfsetspeed \- -get and set terminal attributes, line control, get and set baud rate -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <termios.h> -.B #include <unistd.h> -.P -.BI "int tcgetattr(int " fd ", struct termios *" termios_p ); -.BI "int tcsetattr(int " fd ", int " optional_actions , -.BI " const struct termios *" termios_p ); -.P -.BI "int tcsendbreak(int " fd ", int " duration ); -.BI "int tcdrain(int " fd ); -.BI "int tcflush(int " fd ", int " queue_selector ); -.BI "int tcflow(int " fd ", int " action ); -.P -.BI "void cfmakeraw(struct termios *" termios_p ); -.P -.BI "speed_t cfgetispeed(const struct termios *" termios_p ); -.BI "speed_t cfgetospeed(const struct termios *" termios_p ); -.P -.BI "int cfsetispeed(struct termios *" termios_p ", speed_t " speed ); -.BI "int cfsetospeed(struct termios *" termios_p ", speed_t " speed ); -.BI "int cfsetspeed(struct termios *" termios_p ", speed_t " speed ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR cfsetspeed (), -.BR cfmakeraw (): -.nf - Since glibc 2.19: - _DEFAULT_SOURCE - glibc 2.19 and earlier: - _BSD_SOURCE -.fi -.SH DESCRIPTION -The termios functions describe a general terminal interface that is -provided to control asynchronous communications ports. -.SS The termios structure -Many of the functions described here have a \fItermios_p\fP argument -that is a pointer to a \fItermios\fP structure. -This structure contains at least the following members: -.P -.in +4n -.EX -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]; /* special characters */ -.EE -.in -.P -The values that may be assigned to these fields are described below. -In the case of the first four bit-mask fields, -the definitions of some of the associated flags that may be set are -exposed only if a specific feature test macro (see -.BR feature_test_macros (7)) -is defined, as noted in brackets ("[]"). -.P -In the descriptions below, "not in POSIX" means that the -value is not specified in POSIX.1-2001, -and "XSI" means that the value is specified in POSIX.1-2001 -as part of the XSI extension. -.P -\fIc_iflag\fP flag constants: -.TP -.B IGNBRK -Ignore BREAK condition on input. -.TP -.B BRKINT -If \fBIGNBRK\fP is set, a BREAK is ignored. -If it is not set -but \fBBRKINT\fP is set, then a BREAK causes the input and output -queues to be flushed, and if the terminal is the controlling -terminal of a foreground process group, it will cause a -\fBSIGINT\fP to be sent to this foreground process group. -When neither \fBIGNBRK\fP nor \fBBRKINT\fP are set, a BREAK -reads as a null byte (\[aq]\e0\[aq]), except when \fBPARMRK\fP is set, -in which case it reads as the sequence \e377 \e0 \e0. -.TP -.B IGNPAR -Ignore framing errors and parity errors. -.TP -.B PARMRK -If this bit is set, input bytes with parity or framing errors are -marked when passed to the program. -This bit is meaningful only when -\fBINPCK\fP is set and \fBIGNPAR\fP is not set. -The way erroneous bytes are marked is with two preceding bytes, -\e377 and \e0. -Thus, the program actually reads three bytes for one -erroneous byte received from the terminal. -If a valid byte has the value \e377, -and \fBISTRIP\fP (see below) is not set, -the program might confuse it with the prefix that marks a -parity error. -Therefore, a valid byte \e377 is passed to the program as two -bytes, \e377 \e377, in this case. -.IP -If neither \fBIGNPAR\fP nor \fBPARMRK\fP -is set, read a character with a parity error or framing error -as \e0. -.TP -.B INPCK -Enable input parity checking. -.TP -.B ISTRIP -Strip off eighth bit. -.TP -.B INLCR -Translate NL to CR on input. -.TP -.B IGNCR -Ignore carriage return on input. -.TP -.B ICRNL -Translate carriage return to newline on input (unless \fBIGNCR\fP is set). -.TP -.B IUCLC -(not in POSIX) Map uppercase characters to lowercase on input. -.TP -.B IXON -Enable XON/XOFF flow control on output. -.TP -.B IXANY -(XSI) Typing any character will restart stopped output. -(The default is to allow just the START character to restart output.) -.TP -.B IXOFF -Enable XON/XOFF flow control on input. -.TP -.B IMAXBEL -(not in POSIX) Ring bell when input queue is full. -Linux does not implement this bit, and acts as if it is always set. -.TP -.BR IUTF8 " (since Linux 2.6.4)" -(not in POSIX) Input is UTF8; -this allows character-erase to be correctly performed in cooked mode. -.P -.I c_oflag -flag constants: -.TP -.B OPOST -Enable implementation-defined output processing. -.TP -.B OLCUC -(not in POSIX) Map lowercase characters to uppercase on output. -.TP -.B ONLCR -(XSI) Map NL to CR-NL on output. -.TP -.B OCRNL -Map CR to NL on output. -.TP -.B ONOCR -Don't output CR at column 0. -.TP -.B ONLRET -The NL character is assumed to do the carriage-return function; -the kernel's idea of the current column is set to 0 -after both NL and CR. -.TP -.B OFILL -Send fill characters for a delay, rather than using a timed delay. -.TP -.B OFDEL -Fill character is ASCII DEL (0177). -If unset, fill character is ASCII NUL (\[aq]\e0\[aq]). -(Not implemented on Linux.) -.TP -.B NLDLY -Newline delay mask. -Values are \fBNL0\fP and \fBNL1\fP. -[requires -.B _BSD_SOURCE -or -.B _SVID_SOURCE -or -.BR _XOPEN_SOURCE ] -.TP -.B CRDLY -Carriage return delay mask. -Values are \fBCR0\fP, \fBCR1\fP, \fBCR2\fP, or \fBCR3\fP. -[requires -.B _BSD_SOURCE -or -.B _SVID_SOURCE -or -.BR _XOPEN_SOURCE ] -.TP -.B TABDLY -Horizontal tab delay mask. -Values are \fBTAB0\fP, \fBTAB1\fP, \fBTAB2\fP, \fBTAB3\fP (or \fBXTABS\fP, -but see the -.B BUGS -section). -A value of TAB3, that is, XTABS, expands tabs to spaces -(with tab stops every eight columns). -[requires -.B _BSD_SOURCE -or -.B _SVID_SOURCE -or -.BR _XOPEN_SOURCE ] -.TP -.B BSDLY -Backspace delay mask. -Values are \fBBS0\fP or \fBBS1\fP. -(Has never been implemented.) -[requires -.B _BSD_SOURCE -or -.B _SVID_SOURCE -or -.BR _XOPEN_SOURCE ] -.TP -.B VTDLY -Vertical tab delay mask. -Values are \fBVT0\fP or \fBVT1\fP. -.TP -.B FFDLY -Form feed delay mask. -Values are \fBFF0\fP or \fBFF1\fP. -[requires -.B _BSD_SOURCE -or -.B _SVID_SOURCE -or -.BR _XOPEN_SOURCE ] -.P -\fIc_cflag\fP flag constants: -.TP -.B CBAUD -(not in POSIX) Baud speed mask (4+1 bits). -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.TP -.B CBAUDEX -(not in POSIX) Extra baud speed mask (1 bit), included in -.BR CBAUD . -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.IP -(POSIX says that the baud speed is stored in the -.I termios -structure without specifying where precisely, and provides -.BR cfgetispeed () -and -.BR cfsetispeed () -for getting at it. -Some systems use bits selected by -.B CBAUD -in -.IR c_cflag , -other systems use separate fields, for example, -.I sg_ispeed -and -.IR sg_ospeed .) -.TP -.B CSIZE -Character size mask. -Values are \fBCS5\fP, \fBCS6\fP, \fBCS7\fP, or \fBCS8\fP. -.TP -.B CSTOPB -Set two stop bits, rather than one. -.TP -.B CREAD -Enable receiver. -.TP -.B PARENB -Enable parity generation on output and parity checking for input. -.TP -.B PARODD -If set, then parity for input and output is odd; -otherwise even parity is used. -.TP -.B HUPCL -Lower modem control lines after last process closes the device (hang up). -.TP -.B CLOCAL -Ignore modem control lines. -.TP -.B LOBLK -(not in POSIX) Block output from a noncurrent shell layer. -For use by \fBshl\fP (shell layers). -(Not implemented on Linux.) -.TP -.B CIBAUD -(not in POSIX) Mask for input speeds. -The values for the -.B CIBAUD -bits are -the same as the values for the -.B CBAUD -bits, shifted left -.B IBSHIFT -bits. -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -(Not implemented in glibc, supported on Linux via -.BR TCGET * -and -.BR TCSET * -ioctls; see -.BR ioctl_tty (2)) -.TP -.B CMSPAR -(not in POSIX) -Use "stick" (mark/space) parity (supported on certain serial -devices): if -.B PARODD -is set, the parity bit is always 1; if -.B PARODD -is not set, then the parity bit is always 0. -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.TP -.B CRTSCTS -(not in POSIX) Enable RTS/CTS (hardware) flow control. -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.P -\fIc_lflag\fP flag constants: -.TP -.B ISIG -When any of the characters INTR, QUIT, SUSP, or DSUSP are received, -generate the corresponding signal. -.TP -.B ICANON -Enable canonical mode (described below). -.TP -.B XCASE -(not in POSIX; not supported under Linux) -If \fBICANON\fP is also set, terminal is uppercase only. -Input is converted to lowercase, except for characters preceded by \e. -On output, uppercase characters are preceded by \e and lowercase -characters are converted to uppercase. -[requires -.B _BSD_SOURCE -or -.B _SVID_SOURCE -or -.BR _XOPEN_SOURCE ] -.\" glibc is probably now wrong to allow -.\" Define -.\" .B _XOPEN_SOURCE -.\" to expose -.\" .BR XCASE . -.TP -.B ECHO -Echo input characters. -.TP -.B ECHOE -If \fBICANON\fP is also set, the ERASE character erases the preceding -input character, and WERASE erases the preceding word. -.TP -.B ECHOK -If \fBICANON\fP is also set, the KILL character erases the current line. -.TP -.B ECHONL -If \fBICANON\fP is also set, echo the NL character even if ECHO is not set. -.TP -.B ECHOCTL -(not in POSIX) If \fBECHO\fP is also set, -terminal special characters other than -TAB, NL, START, and STOP are echoed as \fB\[ha]X\fP, -where X is the character with -ASCII code 0x40 greater than the special character. -For example, character -0x08 (BS) is echoed as \fB\[ha]H\fP. -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.TP -.B ECHOPRT -(not in POSIX) If \fBICANON\fP and \fBECHO\fP are also set, characters -are printed as they are being erased. -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.TP -.B ECHOKE -(not in POSIX) If \fBICANON\fP is also set, KILL is echoed by erasing -each character on the line, as specified by \fBECHOE\fP and \fBECHOPRT\fP. -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.TP -.B DEFECHO -(not in POSIX) Echo only when a process is reading. -(Not implemented on Linux.) -.TP -.B FLUSHO -(not in POSIX; not supported under Linux) -Output is being flushed. -This flag is toggled by typing -the DISCARD character. -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.TP -.B NOFLSH -Disable flushing the input and output queues when generating signals for the -INT, QUIT, and SUSP characters. -.\" Stevens lets SUSP only flush the input queue -.TP -.B TOSTOP -Send the -.B SIGTTOU -signal to the process group of a background process -which tries to write to its controlling terminal. -.TP -.B PENDIN -(not in POSIX; not supported under Linux) -All characters in the input queue are reprinted when -the next character is read. -.RB ( bash (1) -handles typeahead this way.) -[requires -.B _BSD_SOURCE -or -.BR _SVID_SOURCE ] -.TP -.B IEXTEN -Enable implementation-defined input processing. -This flag, as well as \fBICANON\fP must be enabled for the -special characters EOL2, LNEXT, REPRINT, WERASE to be interpreted, -and for the \fBIUCLC\fP flag to be effective. -.P -The \fIc_cc\fP array defines the terminal special characters. -The symbolic indices (initial values) and meaning are: -.TP -.B VDISCARD -(not in POSIX; not supported under Linux; 017, SI, Ctrl-O) -Toggle: start/stop discarding pending output. -Recognized when -.B IEXTEN -is set, and then not passed as input. -.TP -.B VDSUSP -(not in POSIX; not supported under Linux; 031, EM, Ctrl-Y) -Delayed suspend character (DSUSP): -send -.B SIGTSTP -signal when the character is read by the user program. -Recognized when -.B IEXTEN -and -.B ISIG -are set, and the system supports -job control, and then not passed as input. -.TP -.B VEOF -(004, EOT, Ctrl-D) -End-of-file character (EOF). -More precisely: this character causes the pending tty buffer to be sent -to the waiting user program without waiting for end-of-line. -If it is the first character of the line, the -.BR read (2) -in the user program returns 0, which signifies end-of-file. -Recognized when -.B ICANON -is set, and then not passed as input. -.TP -.B VEOL -(0, NUL) -Additional end-of-line character (EOL). -Recognized when -.B ICANON -is set. -.TP -.B VEOL2 -(not in POSIX; 0, NUL) -Yet another end-of-line character (EOL2). -Recognized when -.B ICANON -is set. -.TP -.B VERASE -(0177, DEL, rubout, or 010, BS, Ctrl-H, or also #) -Erase character (ERASE). -This erases the previous not-yet-erased character, -but does not erase past EOF or beginning-of-line. -Recognized when -.B ICANON -is set, and then not passed as input. -.TP -.B VINTR -(003, ETX, Ctrl-C, or also 0177, DEL, rubout) -Interrupt character (INTR). -Send a -.B SIGINT -signal. -Recognized when -.B ISIG -is set, and then not passed as input. -.TP -.B VKILL -(025, NAK, Ctrl-U, or Ctrl-X, or also @) -Kill character (KILL). -This erases the input since the last EOF or beginning-of-line. -Recognized when -.B ICANON -is set, and then not passed as input. -.TP -.B VLNEXT -(not in POSIX; 026, SYN, Ctrl-V) -Literal next (LNEXT). -Quotes the next input character, depriving it of -a possible special meaning. -Recognized when -.B IEXTEN -is set, and then not passed as input. -.TP -.B VMIN -Minimum number of characters for noncanonical read (MIN). -.TP -.B VQUIT -(034, FS, Ctrl-\e) -Quit character (QUIT). -Send -.B SIGQUIT -signal. -Recognized when -.B ISIG -is set, and then not passed as input. -.TP -.B VREPRINT -(not in POSIX; 022, DC2, Ctrl-R) -Reprint unread characters (REPRINT). -Recognized when -.B ICANON -and -.B IEXTEN -are set, and then not passed as input. -.TP -.B VSTART -(021, DC1, Ctrl-Q) -Start character (START). -Restarts output stopped by the Stop character. -Recognized when -.B IXON -is set, and then not passed as input. -.TP -.B VSTATUS -(not in POSIX; not supported under Linux; -status request: 024, DC4, Ctrl-T). -Status character (STATUS). -Display status information at terminal, -including state of foreground process and amount of CPU time it has consumed. -Also sends a -.B SIGINFO -signal (not supported on Linux) to the foreground process group. -.TP -.B VSTOP -(023, DC3, Ctrl-S) -Stop character (STOP). -Stop output until Start character typed. -Recognized when -.B IXON -is set, and then not passed as input. -.TP -.B VSUSP -(032, SUB, Ctrl-Z) -Suspend character (SUSP). -Send -.B SIGTSTP -signal. -Recognized when -.B ISIG -is set, and then not passed as input. -.TP -.B VSWTCH -(not in POSIX; not supported under Linux; 0, NUL) -Switch character (SWTCH). -Used in System V to switch shells in -.IR "shell layers" , -a predecessor to shell job control. -.TP -.B VTIME -Timeout in deciseconds for noncanonical read (TIME). -.TP -.B VWERASE -(not in POSIX; 027, ETB, Ctrl-W) -Word erase (WERASE). -Recognized when -.B ICANON -and -.B IEXTEN -are set, and then not passed as input. -.P -An individual terminal special character can be disabled by setting -the value of the corresponding -.I c_cc -element to -.BR _POSIX_VDISABLE . -.P -The above symbolic subscript values are all different, except that -.BR VTIME , -.B VMIN -may have the same value as -.BR VEOL , -.BR VEOF , -respectively. -In noncanonical mode the special character meaning is replaced -by the timeout meaning. -For an explanation of -.B VMIN -and -.BR VTIME , -see the description of -noncanonical mode below. -.SS Retrieving and changing terminal settings -.BR tcgetattr () -gets the parameters associated with the object referred by \fIfd\fP and -stores them in the \fItermios\fP structure referenced by -\fItermios_p\fP. -This function may be invoked from a background process; -however, the terminal attributes may be subsequently changed by a -foreground process. -.P -.BR tcsetattr () -sets the parameters associated with the terminal (unless support is -required from the underlying hardware that is not available) from the -\fItermios\fP structure referred to by \fItermios_p\fP. -\fIoptional_actions\fP specifies when the changes take effect: -.TP -.B TCSANOW -the change occurs immediately. -.TP -.B TCSADRAIN -the change occurs after all output written to -.I fd -has been transmitted. -This option should be used when changing -parameters that affect output. -.TP -.B TCSAFLUSH -the change occurs after all output written to the object referred by -.I fd -has been transmitted, and all input that has been received but not read -will be discarded before the change is made. -.SS Canonical and noncanonical mode -The setting of the -.B ICANON -canon flag in -.I c_lflag -determines whether the terminal is operating in canonical mode -.RB ( ICANON -set) or -noncanonical mode -.RB ( ICANON -unset). -By default, -.B ICANON -is set. -.P -In canonical mode: -.IP \[bu] 3 -Input is made available line by line. -An input line is available when one of the line delimiters -is typed (NL, EOL, EOL2; or EOF at the start of line). -Except in the case of EOF, the line delimiter is included -in the buffer returned by -.BR read (2). -.IP \[bu] -Line editing is enabled (ERASE, KILL; -and if the -.B IEXTEN -flag is set: WERASE, REPRINT, LNEXT). -A -.BR read (2) -returns at most one line of input; if the -.BR read (2) -requested fewer bytes than are available in the current line of input, -then only as many bytes as requested are read, -and the remaining characters will be available for a future -.BR read (2). -.IP \[bu] -The maximum line length is 4096 chars -(including the terminating newline character); -lines longer than 4096 chars are truncated. -After 4095 characters, input processing (e.g., -.B ISIG -and -.B ECHO* -processing) continues, but any input data after 4095 characters up to -(but not including) any terminating newline is discarded. -This ensures that the terminal can always receive -more input until at least one line can be read. -.P -In noncanonical mode input is available immediately (without -the user having to type a line-delimiter character), -no input processing is performed, -and line editing is disabled. -The read buffer will only accept 4095 chars; this provides the -necessary space for a newline char if the input mode is switched -to canonical. -The settings of MIN -.RI ( c_cc[VMIN] ) -and TIME -.RI ( c_cc[VTIME] ) -determine the circumstances in which a -.BR read (2) -completes; there are four distinct cases: -.TP -MIN == 0, TIME == 0 (polling read) -If data is available, -.BR read (2) -returns immediately, with the lesser of the number of bytes -available, or the number of bytes requested. -If no data is available, -.BR read (2) -returns 0. -.TP -MIN > 0, TIME == 0 (blocking read) -.BR read (2) -blocks until MIN bytes are available, -and returns up to the number of bytes requested. -.TP -MIN == 0, TIME > 0 (read with timeout) -TIME specifies the limit for a timer in tenths of a second. -The timer is started when -.BR read (2) -is called. -.BR read (2) -returns either when at least one byte of data is available, -or when the timer expires. -If the timer expires without any input becoming available, -.BR read (2) -returns 0. -If data is already available at the time of the call to -.BR read (2), -the call behaves as though the data was received immediately after the call. -.TP -MIN > 0, TIME > 0 (read with interbyte timeout) -TIME specifies the limit for a timer in tenths of a second. -Once an initial byte of input becomes available, -the timer is restarted after each further byte is received. -.BR read (2) -returns when any of the following conditions is met: -.RS -.IP \[bu] 3 -MIN bytes have been received. -.IP \[bu] -The interbyte timer expires. -.IP \[bu] -The number of bytes requested by -.BR read (2) -has been received. -(POSIX does not specify this termination condition, -and on some other implementations -.\" e.g., Solaris -.BR read (2) -does not return in this case.) -.RE -.IP -Because the timer is started only after the initial byte -becomes available, at least one byte will be read. -If data is already available at the time of the call to -.BR read (2), -the call behaves as though the data was received immediately after the call. -.P -POSIX -.\" POSIX.1-2008 XBD 11.1.7 -does not specify whether the setting of the -.B O_NONBLOCK -file status flag takes precedence over the MIN and TIME settings. -If -.B O_NONBLOCK -is set, a -.BR read (2) -in noncanonical mode may return immediately, -regardless of the setting of MIN or TIME. -Furthermore, if no data is available, -POSIX permits a -.BR read (2) -in noncanonical mode to return either 0, or \-1 with -.I errno -set to -.BR EAGAIN . -.SS Raw mode -.BR cfmakeraw () -sets the terminal to something like the -"raw" mode of the old Version 7 terminal driver: -input is available character by character, -echoing is disabled, and all special processing of -terminal input and output characters is disabled. -The terminal attributes are set as follows: -.P -.in +4n -.EX -termios_p\->c_iflag &= \[ti](IGNBRK | BRKINT | PARMRK | ISTRIP - | INLCR | IGNCR | ICRNL | IXON); -termios_p\->c_oflag &= \[ti]OPOST; -termios_p\->c_lflag &= \[ti](ECHO | ECHONL | ICANON | ISIG | IEXTEN); -termios_p\->c_cflag &= \[ti](CSIZE | PARENB); -termios_p\->c_cflag |= CS8; -.EE -.in -.\" -.SS Line control -.BR tcsendbreak () -transmits a continuous stream of zero-valued bits for a specific -duration, if the terminal is using asynchronous serial data -transmission. -If \fIduration\fP is zero, it transmits zero-valued bits -for at least 0.25 seconds, and not more than 0.5 seconds. -If \fIduration\fP is not zero, it sends zero-valued bits for some -implementation-defined length of time. -.P -If the terminal is not using asynchronous serial data transmission, -.BR tcsendbreak () -returns without taking any action. -.P -.BR tcdrain () -waits until all output written to the object referred to by -.I fd -has been transmitted. -.P -.BR tcflush () -discards data written to the object referred to by -.I fd -but not transmitted, or data received but not read, depending on the -value of -.IR queue_selector : -.TP -.B TCIFLUSH -flushes data received but not read. -.TP -.B TCOFLUSH -flushes data written but not transmitted. -.TP -.B TCIOFLUSH -flushes both data received but not read, and data written but not -transmitted. -.P -.BR tcflow () -suspends transmission or reception of data on the object referred to by -.IR fd , -depending on the value of -.IR action : -.TP -.B TCOOFF -suspends output. -.TP -.B TCOON -restarts suspended output. -.TP -.B TCIOFF -transmits a STOP character, which stops the terminal device from -transmitting data to the system. -.TP -.B TCION -transmits a START character, which starts the terminal device -transmitting data to the system. -.P -The default on open of a terminal file is that neither its input nor its -output is suspended. -.SS Line speed -The baud rate functions are provided for getting and setting the values -of the input and output baud rates in the \fItermios\fP structure. -The new values do not take effect -until -.BR tcsetattr () -is successfully called. -.P -Setting the speed to \fBB0\fP instructs the modem to "hang up". -The actual bit rate corresponding to \fBB38400\fP may be altered with -.BR setserial (8). -.P -The input and output baud rates are stored in the \fItermios\fP -structure. -.P -.BR cfgetospeed () -returns the output baud rate stored in the \fItermios\fP structure -pointed to by -.IR termios_p . -.P -.BR cfsetospeed () -sets the output baud rate stored in the \fItermios\fP structure pointed -to by \fItermios_p\fP to \fIspeed\fP, which must be one of these constants: -.RS -.TP -.B B0 -.TQ -.B B50 -.TQ -.B B75 -.TQ -.B B110 -.TQ -.B B134 -.TQ -.B B150 -.TQ -.B B200 -.TQ -.B B300 -.TQ -.B B600 -.TQ -.B B1200 -.TQ -.B B1800 -.TQ -.B B2400 -.TQ -.B B4800 -.TQ -.B B9600 -.TQ -.B B19200 -.TQ -.B B38400 -.TQ -.B B57600 -.TQ -.B B115200 -.TQ -.B B230400 -.TQ -.B B460800 -.TQ -.B B500000 -.TQ -.B B576000 -.TQ -.B B921600 -.TQ -.B B1000000 -.TQ -.B B1152000 -.TQ -.B B1500000 -.TQ -.B B2000000 -.RE -.P -These constants are additionally supported on the SPARC architecture: -.RS -.TP -.B B76800 -.TQ -.B B153600 -.TQ -.B B307200 -.TQ -.B B614400 -.RE -.P -These constants are additionally supported on non-SPARC architectures: -.RS -.TP -.B B2500000 -.TQ -.B B3000000 -.TQ -.B B3500000 -.TQ -.B B4000000 -.RE -.P -Due to differences between architectures, portable applications should check -if a particular -.BI B nnn -constant is defined prior to using it. -.P -The zero baud rate, -.BR B0 , -is used to terminate the connection. -If -.B B0 -is specified, the modem control lines shall no longer be asserted. -Normally, this will disconnect the line. -.B CBAUDEX -is a mask -for the speeds beyond those defined in POSIX.1 (57600 and above). -Thus, -.BR B57600 " & " CBAUDEX -is nonzero. -.P -Setting the baud rate to a value other than those defined by -.BI B nnn -constants is possible via the -.B TCSETS2 -ioctl; see -.BR ioctl_tty (2). -.P -.BR cfgetispeed () -returns the input baud rate stored in the -.I termios -structure. -.P -.BR cfsetispeed () -sets the input baud rate stored in the -.I termios -structure to -.IR speed , -which must be specified as one of the -.BI B nnn -constants listed above for -.BR cfsetospeed (). -If the input baud rate is set to the literal constant -.B 0 -(not the symbolic constant -.BR B0 ), -the input baud rate will be -equal to the output baud rate. -.P -.BR cfsetspeed () -is a 4.4BSD extension. -It takes the same arguments as -.BR cfsetispeed (), -and sets both input and output speed. -.SH RETURN VALUE -.BR cfgetispeed () -returns the input baud rate stored in the -\fItermios\fP -structure. -.P -.BR cfgetospeed () -returns the output baud rate stored in the \fItermios\fP structure. -.P -All other functions return: -.TP -.B 0 -on success. -.TP -.B \-1 -on failure and set -.I errno -to indicate the error. -.P -Note that -.BR tcsetattr () -returns success if \fIany\fP of the requested changes could be -successfully carried out. -Therefore, when making multiple changes -it may be necessary to follow this call with a further call to -.BR tcgetattr () -to check that all changes have been performed successfully. -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR tcgetattr (), -.BR tcsetattr (), -.BR tcdrain (), -.BR tcflush (), -.BR tcflow (), -.BR tcsendbreak (), -.BR cfmakeraw (), -.BR cfgetispeed (), -.BR cfgetospeed (), -.BR cfsetispeed (), -.BR cfsetospeed (), -.BR cfsetspeed () -T} Thread safety MT-Safe -.TE -.\" FIXME: The markings are different from that in the glibc manual. -.\" markings in glibc manual are more detailed: -.\" -.\" tcsendbreak: MT-Unsafe race:tcattr(filedes)/bsd -.\" tcflow: MT-Unsafe race:tcattr(filedes)/bsd -.\" -.\" glibc manual says /bsd indicate the preceding marker only applies -.\" when the underlying kernel is a BSD kernel. -.\" So, it is safety in Linux kernel. -.SH STANDARDS -.TP -.BR tcgetattr () -.TQ -.BR tcsetattr () -.TQ -.BR tcsendbreak () -.TQ -.BR tcdrain () -.TQ -.BR tcflush () -.TQ -.BR tcflow () -.TQ -.BR cfgetispeed () -.TQ -.BR cfgetospeed () -.TQ -.BR cfsetispeed () -.TQ -.BR cfsetospeed () -POSIX.1-2008. -.TP -.BR cfmakeraw () -.TQ -.BR cfsetspeed () -BSD. -.SH HISTORY -.TP -.BR tcgetattr () -.TQ -.BR tcsetattr () -.TQ -.BR tcsendbreak () -.TQ -.BR tcdrain () -.TQ -.BR tcflush () -.TQ -.BR tcflow () -.TQ -.BR cfgetispeed () -.TQ -.BR cfgetospeed () -.TQ -.BR cfsetispeed () -.TQ -.BR cfsetospeed () -POSIX.1-2001. -.TP -.BR cfmakeraw () -.TQ -.BR cfsetspeed () -BSD. -.SH NOTES -UNIX\ V7 and several later systems have a list of baud rates -where after the values -.B B0 -through -.B B9600 -one finds the two constants -.BR EXTA , -.B EXTB -("External A" and "External B"). -Many systems extend the list with much higher baud rates. -.P -The effect of a nonzero \fIduration\fP with -.BR tcsendbreak () -varies. -SunOS specifies a break of -.I "duration\ *\ N" -seconds, where \fIN\fP is at least 0.25, and not more than 0.5. -Linux, AIX, DU, Tru64 send a break of -.I duration -milliseconds. -FreeBSD and NetBSD and HP-UX and MacOS ignore the value of -.IR duration . -Under Solaris and UnixWare, -.BR tcsendbreak () -with nonzero -.I duration -behaves like -.BR tcdrain (). -.\" libc4 until 4.7.5, glibc for sysv: EINVAL for duration > 0. -.\" libc4.7.6, libc5, glibc for unix: duration in ms. -.\" glibc for bsd: duration in us -.\" glibc for sunos4: ignore duration -.SH BUGS -.\" kernel 77e5bff1640432f28794a00800955e646dcd7455 -.\" glibc 573963e32ffac46d9891970ddebde2ac3212c5c0 -On the Alpha architecture before Linux 4.16 (and glibc before glibc 2.28), the -.B XTABS -value was different from -.B TAB3 -and it was ignored by the -.B N_TTY -line discipline code of the terminal driver as a result -(because as it wasn't part of the -.B TABDLY -mask). -.SH SEE ALSO -.BR reset (1), -.BR setterm (1), -.BR stty (1), -.BR tput (1), -.BR tset (1), -.BR tty (1), -.BR ioctl_console (2), -.BR ioctl_tty (2), -.BR cc_t (3type), -.BR speed_t (3type), -.BR tcflag_t (3type), -.BR setserial (8) |