+++ /dev/null
-.\" Copyright 2002 Walter Harms <walter.harms@informatik.uni-oldenburg.de>
-.\" and Andries Brouwer <aeb@cwi.nl>.
-.\"
-.\" %%%LICENSE_START(GPL_NOVERSION_ONELINE)
-.\" Distributed under GPL
-.\" %%%LICENSE_END
-.\"
-.TH TTY_IOCTL 4 2013-11-12 "Linux" "Linux Programmer's Manual"
-.SH NAME
-tty_ioctl \- ioctls for terminals and serial lines
-.SH SYNOPSIS
-.B "#include <termios.h>"
-.sp
-.BI "int ioctl(int " fd ", int " cmd ", ...);"
-.SH DESCRIPTION
-The
-.BR ioctl (2)
-call for terminals and serial ports accepts many possible command arguments.
-Most require a third argument, of varying type, here called
-.I argp
-or
-.IR arg .
-.LP
-Use of
-.I ioctl
-makes for nonportable programs.
-Use the POSIX interface described in
-.BR termios (3)
-whenever possible.
-.SS Get and set terminal attributes
-.TP
-.BI "TCGETS struct termios *" argp
-Equivalent to
-.IR "tcgetattr(fd, argp)" .
-.br
-Get the current serial port settings.
-.TP
-.BI "TCSETS const struct termios *" argp
-Equivalent to
-.IR "tcsetattr(fd, TCSANOW, argp)" .
-.br
-Set the current serial port settings.
-.TP
-.BI "TCSETSW const struct termios *" argp
-Equivalent to
-.IR "tcsetattr(fd, TCSADRAIN, argp)" .
-.br
-Allow the output buffer to drain, and
-set the current serial port settings.
-.TP
-.BI "TCSETSF const struct termios *" argp
-Equivalent to
-.IR "tcsetattr(fd, TCSAFLUSH, argp)" .
-.br
-Allow the output buffer to drain, discard pending input, and
-set the current serial port settings.
-.LP
-The following four ioctls are just like
-.BR TCGETS ,
-.BR TCSETS ,
-.BR TCSETSW ,
-.BR TCSETSF ,
-except that they take a
-.I "struct termio\ *"
-instead of a
-.IR "struct termios\ *" .
-.IP
-.BI "TCGETA struct termio *" argp
-.IP
-.BI "TCSETA const struct termio *" argp
-.IP
-.BI "TCSETAW const struct termio *" argp
-.IP
-.BI "TCSETAF const struct termio *" argp
-.SS Locking the termios structure
-The
-.I termios
-structure of a terminal can be locked.
-The lock is itself a
-.I termios
-structure, with nonzero bits or fields indicating a
-locked value.
-.TP
-.BI "TIOCGLCKTRMIOS struct termios *" argp
-Gets the locking status of the
-.I termios
-structure of the terminal.
-.TP
-.BI "TIOCSLCKTRMIOS const struct termios *" argp
-Sets the locking status of the
-.I termios
-structure of the terminal.
-Only a process with the
-.BR CAP_SYS_ADMIN
-capability can do this.
-.SS Get and set window size
-Window sizes are kept in the kernel, but not used by the kernel
-(except in the case of virtual consoles, where the kernel will
-update the window size when the size of the virtual console changes,
-for example, by loading a new font).
-
-The following constants and structure are defined in
-.IR <sys/ioctl.h> .
-.TP
-.BI "TIOCGWINSZ struct winsize *" argp
-Get window size.
-.TP
-.BI "TIOCSWINSZ const struct winsize *" argp
-Set window size.
-.LP
-The struct used by these ioctls is defined as
-
-.in +4n
-.nf
-struct winsize {
- unsigned short ws_row;
- unsigned short ws_col;
- unsigned short ws_xpixel; /* unused */
- unsigned short ws_ypixel; /* unused */
-};
-.fi
-.in
-
-When the window size changes, a
-.B SIGWINCH
-signal is sent to the
-foreground process group.
-.SS Sending a break
-.TP
-.BI "TCSBRK int " arg
-Equivalent to
-.IR "tcsendbreak(fd, arg)" .
-.br
-If the terminal is using asynchronous serial data transmission, and
-.I arg
-is zero, then send a break (a stream of zero bits) for between
-0.25 and 0.5 seconds.
-If the terminal is not using asynchronous
-serial data transmission, then either a break is sent, or the function
-returns without doing anything.
-When
-.I arg
-is nonzero, nobody knows what will happen.
-
-(SVr4, UnixWare, Solaris, Linux treat
-.I "tcsendbreak(fd,arg)"
-with nonzero
-.I arg
-like
-.IR "tcdrain(fd)" .
-SunOS treats
-.I arg
-as a multiplier, and sends a stream of bits
-.I arg
-times as long as done for zero
-.IR arg .
-DG/UX and AIX treat
-.I arg
-(when nonzero) as a time interval measured in milliseconds.
-HP-UX ignores
-.IR arg .)
-.TP
-.BI "TCSBRKP int " arg
-So-called "POSIX version" of
-.BR TCSBRK .
-It treats nonzero
-.I arg
-as a timeinterval measured in deciseconds, and does nothing
-when the driver does not support breaks.
-.TP
-.B "TIOCSBRK void"
-Turn break on, that is, start sending zero bits.
-.TP
-.B "TIOCCBRK void"
-Turn break off, that is, stop sending zero bits.
-.SS Software flow control
-.TP
-.BI "TCXONC int " arg
-Equivalent to
-.IR "tcflow(fd, arg)" .
-.br
-See
-.BR tcflow (3)
-for the argument values
-.BR TCOOFF ,
-.BR TCOON ,
-.BR TCIOFF ,
-.BR TCION .
-.SS Buffer count and flushing
-.TP
-.BI "FIONREAD int *" argp
-Get the number of bytes in the input buffer.
-.TP
-.BI "TIOCINQ int *" argp
-Same as
-.BR FIONREAD .
-.TP
-.BI "TIOCOUTQ int *" argp
-Get the number of bytes in the output buffer.
-.TP
-.BI "TCFLSH int " arg
-Equivalent to
-.IR "tcflush(fd, arg)" .
-.br
-See
-.BR tcflush (3)
-for the argument values
-.BR TCIFLUSH ,
-.BR TCOFLUSH ,
-.BR TCIOFLUSH .
-.SS Faking input
-.TP
-.BI "TIOCSTI const char *" argp
-Insert the given byte in the input queue.
-.SS Redirecting console output
-.TP
-.B "TIOCCONS void"
-Redirect output that would have gone to
-.I /dev/console
-or
-.I /dev/tty0
-to the given terminal.
-If that was a pseudoterminal master, send it to the slave.
-In Linux before version 2.6.10,
-anybody can do this as long as the output was not redirected yet;
-since version 2.6.10, only a process with the
-.BR CAP_SYS_ADMIN
-capability may do this.
-If output was redirected already
-.B EBUSY
-is returned,
-but redirection can be stopped by using this ioctl with
-.I fd
-pointing at
-.I /dev/console
-or
-.IR /dev/tty0 .
-.SS Controlling terminal
-.TP
-.BI "TIOCSCTTY int " arg
-Make the given terminal the controlling terminal of the calling process.
-The calling process must be a session leader and not have a
-controlling terminal already.
-For this case,
-.I arg
-should be specified as zero.
-
-If this terminal is already the controlling terminal
-of a different session group, then the ioctl fails with
-.BR EPERM ,
-unless the caller has the
-.BR CAP_SYS_ADMIN
-capability and
-.I arg
-equals 1, in which case the terminal is stolen, and all processes that had
-it as controlling terminal lose it.
-.TP
-.B "TIOCNOTTY void"
-If the given terminal was the controlling terminal of the calling process,
-give up this controlling terminal.
-If the process was session leader,
-then send
-.B SIGHUP
-and
-.B SIGCONT
-to the foreground process group
-and all processes in the current session lose their controlling terminal.
-.SS Process group and session ID
-.TP
-.BI "TIOCGPGRP pid_t *" argp
-When successful, equivalent to
-.IR "*argp = tcgetpgrp(fd)" .
-.br
-Get the process group ID of the foreground process group on this terminal.
-.TP
-.BI "TIOCSPGRP const pid_t *" argp
-Equivalent to
-.IR "tcsetpgrp(fd, *argp)" .
-.br
-Set the foreground process group ID of this terminal.
-.TP
-.BI "TIOCGSID pid_t *" argp
-Get the session ID of the given terminal.
-This will fail with
-.B ENOTTY
-in case the terminal is not a master pseudoterminal
-and not our controlling terminal.
-Strange.
-.SS Exclusive mode
-.TP
-.B "TIOCEXCL void"
-Put the terminal into exclusive mode.
-No further
-.BR open (2)
-operations on the terminal are permitted.
-(They will fail with
-.BR EBUSY ,
-except for a process with the
-.BR CAP_SYS_ADMIN
-capability.)
-.TP
-.B "TIOCNXCL void"
-Disable exclusive mode.
-.SS Line discipline
-.TP
-.BI "TIOCGETD int *" argp
-Get the line discipline of the terminal.
-.TP
-.BI "TIOCSETD const int *" argp
-Set the line discipline of the terminal.
-.SS Pseudoterminal ioctls
-.TP
-.BI "TIOCPKT const int *" argp
-Enable (when
-.RI * argp
-is nonzero) or disable packet mode.
-Can be applied to the master side of a pseudoterminal only (and will return
-.B ENOTTY
-otherwise).
-In packet mode, each subsequent
-.BR read (2)
-will return a packet that either contains a single nonzero control byte,
-or has a single byte containing zero (\(aq\0\(aq) followed by data
-written on the slave side of the pseudoterminal.
-If the first byte is not
-.B TIOCPKT_DATA
-(0), it is an OR of one
-or more of the following bits:
-
-.nf
-TIOCPKT_FLUSHREAD The read queue for the terminal is flushed.
-TIOCPKT_FLUSHWRITE The write queue for the terminal is flushed.
-TIOCPKT_STOP Output to the terminal is stopped.
-TIOCPKT_START Output to the terminal is restarted.
-TIOCPKT_DOSTOP The start and stop characters are \fB^S\fP/\fB^Q\fP.
-TIOCPKT_NOSTOP The start and stop characters are not \fB^S\fP/\fB^Q\fP.
-.fi
-
-While this mode is in use, the presence
-of control status information to be read
-from the master side may be detected by a
-.BR select (2)
-for exceptional conditions.
-
-This mode is used by
-.BR rlogin (1)
-and
-.BR rlogind (8)
-to implement a remote-echoed,
-locally \fB^S\fP/\fB^Q\fP flow-controlled remote login.
-
-The BSD ioctls
-.BR TIOCSTOP ,
-.BR TIOCSTART ,
-.BR TIOCUCNTL ,
-.B TIOCREMOTE
-have not been implemented under Linux.
-.SS Modem control
-.TP
-.BI "TIOCMGET int *" argp
-get the status of modem bits.
-.TP
-.BI "TIOCMSET const int *" argp
-set the status of modem bits.
-.TP
-.BI "TIOCMBIC const int *" argp
-clear the indicated modem bits.
-.TP
-.BI "TIOCMBIS const int *" argp
-set the indicated modem bits.
-.LP
-Bits used by these four ioctls:
-
-.nf
-TIOCM_LE DSR (data set ready/line enable)
-TIOCM_DTR DTR (data terminal ready)
-TIOCM_RTS RTS (request to send)
-TIOCM_ST Secondary TXD (transmit)
-TIOCM_SR Secondary RXD (receive)
-TIOCM_CTS CTS (clear to send)
-TIOCM_CAR DCD (data carrier detect)
-TIOCM_CD see TIOCM_CAR
-TIOCM_RNG RNG (ring)
-TIOCM_RI see TIOCM_RNG
-TIOCM_DSR DSR (data set ready)
-.fi
-.SS Marking a line as local
-.TP
-.BI "TIOCGSOFTCAR int *" argp
-("Get software carrier flag")
-Get the status of the CLOCAL flag in the c_cflag field of the
-.I termios
-structure.
-.TP
-.BI "TIOCSSOFTCAR const int *" argp
-("Set software carrier flag")
-Set the CLOCAL flag in the
-.I termios
-structure when
-.RI * argp
-is nonzero, and clear it otherwise.
-.LP
-If the
-.B CLOCAL
-flag for a line is off, the hardware carrier detect (DCD)
-signal is significant, and an
-.BR open (2)
-of the corresponding terminal will block until DCD is asserted,
-unless the
-.B O_NONBLOCK
-flag is given.
-If
-.B CLOCAL
-is set, the line behaves as if DCD is always asserted.
-The software carrier flag is usually turned on for local devices,
-and is off for lines with modems.
-.SS Linux-specific
-For the
-.B TIOCLINUX
-ioctl, see
-.BR console_ioctl (4).
-.SS Kernel debugging
-.B "#include <linux/tty.h>"
-.TP
-.BI "TIOCTTYGSTRUCT struct tty_struct *" argp
-Get the
-.I tty_struct
-corresponding to
-.IR fd .
-.\"
-.\" .SS "Serial info"
-.\" .BR "#include <linux/serial.h>"
-.\" .sp
-.\" .TP
-.\" .BI "TIOCGSERIAL struct serial_struct *" argp
-.\" Get serial info.
-.\" .TP
-.\" .BI "TIOCSSERIAL const struct serial_struct *" argp
-.\" Set serial info.
-.SH RETURN VALUE
-The
-.BR ioctl (2)
-system call returns 0 on success.
-On error, it returns \-1 and sets
-.I errno
-appropriately.
-.SH ERRORS
-.TP
-.B EINVAL
-Invalid command parameter.
-.TP
-.B ENOIOCTLCMD
-Unknown command.
-.TP
-.B ENOTTY
-Inappropriate
-.IR fd .
-.TP
-.B EPERM
-Insufficient permission.
-.SH EXAMPLE
-Check the condition of DTR on the serial port.
-
-.nf
-#include <termios.h>
-#include <fcntl.h>
-#include <sys/ioctl.h>
-
-int
-main(void)
-{
- int fd, serial;
-
- fd = open("/dev/ttyS0", O_RDONLY);
- ioctl(fd, TIOCMGET, &serial);
- if (serial & TIOCM_DTR)
- puts("TIOCM_DTR is not set");
- else
- puts("TIOCM_DTR is set");
- close(fd);
-}
-.fi
-.SH SEE ALSO
-.BR ioctl (2),
-.BR termios (3),
-.BR console_ioctl (4),
-.BR pty (7)
-.\"
-.\" FIONBIO const int *
-.\" FIONCLEX void
-.\" FIOCLEX void
-.\" FIOASYNC const int *
-.\" from serial.c:
-.\" TIOCSERCONFIG void
-.\" TIOCSERGWILD int *
-.\" TIOCSERSWILD const int *
-.\" TIOCSERGSTRUCT struct async_struct *
-.\" TIOCSERGETLSR int *
-.\" TIOCSERGETMULTI struct serial_multiport_struct *
-.\" TIOCSERSETMULTI const struct serial_multiport_struct *
-.\" TIOCGSERIAL, TIOCSSERIAL (see above)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
OSDN Git Service
