Termios For Windows

The termios functions describe a general terminal interface that is provided to control asynchronous communications ports. Many of the functions described here have a termiosp argument that is a pointer to a termios structure.

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

A native Windows port of the GNU Compiler Collection (GCC). ACCHECKHEADERS(unistd.h stdlib.h stdarg.h varargs.h limits.h string.h memory.h locale.h termcap.h termio.h termios.h dlfcn.h stddef.h netdb.h) That's seems very common, but: checking for unistd.h. Yes checking for stdlib.h. Yes checking for stdarg.h. Yes checking for.
TermiWin is a library which purpose is to allow you to use on a Windows system, the same code used in Linux to communicate with a device through a serial port. This is possible because termios’s functions have been rewritten to be compatible with Windows’s COM functions.

Synopsis

Feature Test Macro Requirements for glibc (seefeature_test_macros(7)):

cfsetspeed(),cfmakeraw():_BSD_SOURCE

Description

The termios functions describe a general terminal interface that isprovided to control asynchronous communications ports.

The termios structure

Many of the functions described here have a termios_p argumentthat is a pointer to a termios structure.This structure contains at least the following members:

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 areexposed only if a specific feature test macro (seefeature_test_macros(7))is defined, as noted in brackets ('[]').

In the descriptions below, 'not in POSIX' means that thevalue is not specified in POSIX.1-2001,and 'XSI' means that the value is specified in POSIX.1-2001as part of the XSI extension.

c_iflag flag constants:

OPOST: Enable implementation-defined output processing.
OLCUC: (not in POSIX) Map lowercase characters to uppercase on output.
ONLCR: (XSI) Map NL to CR-NL on output.
OCRNL: Map CR to NL on output.
ONOCR: Don't output CR at column 0.
ONLRET: Don't output CR.
OFILL: Send fill characters for a delay, rather than using a timed delay.
OFDEL: Fill character is ASCII DEL (0177).If unset, fill character is ASCII NUL (aq0aq).(Not implemented on Linux.)
NLDLY: Newline delay mask.Values are NL0 and NL1.[requires_BSD_SOURCEor_SVID_SOURCEor_XOPEN_SOURCE]
CRDLY: Carriage return delay mask.Values are CR0, CR1, CR2, or CR3.[requires_BSD_SOURCEor_SVID_SOURCEor_XOPEN_SOURCE]
TABDLY: Horizontal tab delay mask.Values are TAB0, TAB1, TAB2, TAB3 (or XTABS).A value of TAB3, that is, XTABS, expands tabs to spaces(with tab stops every eight columns).[requires_BSD_SOURCEor_SVID_SOURCEor_XOPEN_SOURCE]
BSDLY: Backspace delay mask.Values are BS0 or BS1.(Has never been implemented.)[requires_BSD_SOURCEor_SVID_SOURCEor_XOPEN_SOURCE]
VTDLY: Vertical tab delay mask.Values are VT0 or VT1.
FFDLY: Form feed delay mask.Values are FF0 or FF1.[requires_BSD_SOURCEor_SVID_SOURCEor_XOPEN_SOURCE]

c_cflag flag constants:

CBAUD

(not in POSIX) Baud speed mask (4+1 bits).[requires_BSD_SOURCEor_SVID_SOURCE]

CBAUDEX

(not in POSIX) Extra baud speed mask (1 bit), included inCBAUD.[requires_BSD_SOURCEor_SVID_SOURCE]

(POSIX says that the baud speed is stored in thetermiosstructure without specifying where precisely, and providescfgetispeed()andcfsetispeed()for getting at it.Some systems use bits selected byCBAUDinc_cflag,other systems use separate fields, for example,sg_ispeedandsg_ospeed.)

CSIZE

Character size mask.Values are CS5, CS6, CS7, or CS8.

CSTOPB

Set two stop bits, rather than one.

CREAD

Enable receiver.

PARENB

Enable parity generation on output and parity checking for input.

PARODD

If set, then parity for input and output is odd;otherwise even parity is used.

HUPCL

Lower modem control lines after last process closes the device (hang up).

CLOCAL

Ignore modem control lines.

LOBLK

(not in POSIX) Block output from a noncurrent shell layer.For use by shl (shell layers). (Not implemented on Linux.)

CIBAUD

(not in POSIX) Mask for input speeds.The values for theCIBAUDbits arethe same as the values for theCBAUDbits, shifted leftIBSHIFTbits.[requires_BSD_SOURCEor_SVID_SOURCE](Not implemented on Linux.)

CMSPAR

(not in POSIX)Use 'stick' (mark/space) parity (supported on certain serialdevices): ifPARODDis set, the parity bit is always 1; ifPARODDis not set, then the parity bit is always 0.[requires_BSD_SOURCEor_SVID_SOURCE]

CRTSCTS

(not in POSIX) Enable RTS/CTS (hardware) flow control.[requires_BSD_SOURCEor_SVID_SOURCE]

c_lflag flag constants:

VDISCARD: (not in POSIX; not supported under Linux; 017, SI, Ctrl-O)Toggle: start/stop discarding pending output.Recognized whenIEXTENis set, and then not passed as input.
VDSUSP: (not in POSIX; not supported under Linux; 031, EM, Ctrl-Y)Delayed suspend character (DSUSP):sendSIGTSTPsignal when the character is read by the user program.Recognized whenIEXTENandISIGare set, and the system supportsjob control, and then not passed as input.
VEOF: (004, EOT, Ctrl-D)End-of-file character (EOF).More precisely: this character causes the pending tty buffer to be sentto the waiting user program without waiting for end-of-line.If it is the first character of the line, theread(2)in the user program returns 0, which signifies end-of-file.Recognized whenICANONis set, and then not passed as input.
VEOL: (0, NUL)Additional end-of-line character (EOL).Recognized whenICANONis set.
VEOL2: (not in POSIX; 0, NUL)Yet another end-of-line character (EOL2).Recognized whenICANONis set.
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 whenICANONis set, and then not passed as input.
VINTR: (003, ETX, Ctrl-C, or also 0177, DEL, rubout)Interrupt character (INTR).Send aSIGINTsignal.Recognized whenISIGis set, and then not passed as input.
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 whenICANONis set, and then not passed as input.
VLNEXT: (not in POSIX; 026, SYN, Ctrl-V)Literal next (LNEXT).Quotes the next input character, depriving it ofa possible special meaning.Recognized whenIEXTENis set, and then not passed as input.
VMIN: Minimum number of characters for noncanonical read (MIN).
VQUIT: (034, FS, Ctrl-)Quit character (QUIT).SendSIGQUITsignal.Recognized whenISIGis set, and then not passed as input.
VREPRINT: (not in POSIX; 022, DC2, Ctrl-R)Reprint unread characters (REPRINT).Recognized whenICANONandIEXTENare set, and then not passed as input.
VSTART: (021, DC1, Ctrl-Q)Start character (START).Restarts output stopped by the Stop character.Recognized whenIXONis set, and then not passed as input.
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 aSIGINFOsignal (not supported on Linux) to the foreground process group.
VSTOP: (023, DC3, Ctrl-S)Stop character (STOP).Stop output until Start character typed.Recognized whenIXONis set, and then not passed as input.
VSUSP: (032, SUB, Ctrl-Z)Suspend character (SUSP).SendSIGTSTPsignal.Recognized whenISIGis set, and then not passed as input.
VSWTCH: (not in POSIX; not supported under Linux; 0, NUL)Switch character (SWTCH).Used in System V to switch shells inshell layers,a predecessor to shell job control.
VTIME: Timeout in deciseconds for noncanonical read (TIME).
VWERASE: (not in POSIX; 027, ETB, Ctrl-W)Word erase (WERASE).Recognized whenICANONandIEXTENare set, and then not passed as input.

An individual terminal special character can be disabled by settingthe value of the correspondingc_ccelement to_POSIX_VDISABLE.

The above symbolic subscript values are all different, except thatVTIME,VMINmay have the same value asVEOL,VEOF,respectively.In noncanonical mode the special character meaning is replacedby the timeout meaning.For an explanation ofVMINandVTIME,see the description ofnoncanonical mode below.

Retrieving and changing terminal settings

tcgetattr()gets the parameters associated with the object referred by fd andstores them in the termios structure referenced bytermios_p.This function may be invoked from a background process;however, the terminal attributes may be subsequently changed by aforeground process.

tcsetattr()sets the parameters associated with the terminal (unless support isrequired from the underlying hardware that is not available) from thetermios structure referred to by termios_p.optional_actions specifies when the changes take effect:

*: Input is made available line by line.An input line is available when one of the line delimitersis typed (NL, EOL, EOL2; or EOF at the start of line).Except in the case of EOF, the line delimiter is includedin the buffer returned byread(2).
*: Line editing is enabled (ERASE, KILL;and if theIEXTENflag is set: WERASE, REPRINT, LNEXT).Aread(2)returns at most one line of input; if theread(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 futureread(2).

In noncanonical mode input is available immediately (withoutthe user having to type a line-delimiter character),no input processing is performed,and line editing is disabled.The settings of MIN(c_cc[VMIN])and TIME(c_cc[VTIME])determine the circumstances in which aread(2)completes; there are four distinct cases:

Line control

tcsendbreak()transmits a continuous stream of zero-valued bits for a specificduration, if the terminal is using asynchronous serial datatransmission.If duration is zero, it transmits zero-valued bitsfor at least 0.25 seconds, and not more that 0.5 seconds.If duration is not zero, it sends zero-valued bits for someimplementation-defined length of time.

If the terminal is not using asynchronous serial data transmission,tcsendbreak()returns without taking any action.

tcdrain()waits until all output written to the object referred to byfdhas been transmitted.

tcflush()discards data written to the object referred to byfdbut not transmitted, or data received but not read, depending on thevalue ofqueue_selector:

TCOOFF: suspends output.
TCOON: restarts suspended output.
TCIOFF: transmits a STOP character, which stops the terminal device fromtransmitting data to the system.
TCION: transmits a START character, which starts the terminal devicetransmitting data to the system.

The default on open of a terminal file is that neither its input nor itsoutput is suspended.

Line speed

The baud rate functions are provided for getting and setting the valuesof the input and output baud rates in the termios structure.The new values do not take effectuntiltcsetattr()is successfully called.

Setting the speed to B0 instructs the modem to 'hang up'.The actual bit rate corresponding to B38400 may be altered withsetserial/wifi-hacker-cydia-repo.html. (8).

The input and output baud rates are stored in the termiosstructure.

cfgetospeed()returns the output baud rate stored in the termios structurepointed to bytermios_p.

cfsetospeed()sets the output baud rate stored in the termios structure pointedto by termios_p to speed, which must be one of these constants:The zero baud rate, B0,is used to terminate the connection.If B0 is specified, the modem control lines shall no longer be asserted.Normally, this will disconnect the line.CBAUDEX is a maskfor the speeds beyond those defined in POSIX.1 (57600 and above).Thus, B57600 & CBAUDEX is nonzero.

cfgetispeed()returns the input baud rate stored in the termios structure.

cfsetispeed()sets the input baud rate stored in the termios structure tospeed,which must be specified as one of the Bnnn constants listed above forcfsetospeed().If the input baud rate is set to zero, the input baud rate will beequal to the output baud rate.

cfsetspeed()is a 4.4BSD extension.It takes the same arguments ascfsetispeed(),and sets both input and output speed.

Return Value

cfgetispeed()returns the input baud rate stored in thetermiosstructure.

cfgetospeed()returns the output baud rate stored in the termios structure.