TTY Functions: Functions to perform common terminal access routines.

Functions
int	tty_read (int fd, char *buf, int nbytes, int timeout, int *nbytes_read)
	read buffer from terminal More...
int	tty_read_section (int fd, char *buf, char stop_char, int timeout, int *nbytes_read)
	read buffer from terminal with a delimiter More...
int	tty_nread_section (int fd, char *buf, int nsize, char stop_char, int timeout, int *nbytes_read)
	read buffer from terminal with a delimiter More...
int	tty_write (int fd, const char *buffer, int nbytes, int *nbytes_written)
	Writes a buffer to fd. More...
int	tty_write_string (int fd, const char *buffer, int *nbytes_written)
	Writes a null terminated string to fd. More...
int	tty_connect (const char *device, int bit_rate, int word_size, int parity, int stop_bits, int *fd)
	Establishes a tty connection to a terminal device. More...
int	tty_disconnect (int fd)
	Closes a tty connection and flushes the bus. More...
void	tty_error_msg (int err_code, char *err_msg, int err_msg_len)
	Retrieve the tty error message. More...
void	tty_set_debug (int debug)
	tty_set_debug Enable or disable debug which prints verbose information. More...
void	tty_set_gemini_udp_format (int enabled)
void	tty_clr_trailing_read_lf (int enabled)
int	tty_timeout (int fd, int timeout)

Detailed Description

Function Documentation

tty_clr_trailing_read_lf()

void tty_clr_trailing_read_lf

(

int

enabled

)

tty_connect()

int tty_connect	(	const char *	device,
		int	bit_rate,
		int	word_size,
		int	parity,
		int	stop_bits,
		int *	fd
	)

Establishes a tty connection to a terminal device.

Parameters

device	the device node. e.g. /dev/ttyS0
bit_rate	bit rate
word_size	number of data bits, 7 or 8, USE 8 DATA BITS with modbus
parity	0=no parity, 1=parity EVEN, 2=parity ODD
stop_bits	number of stop bits : 1 or 2
fd	fd is set to the file descriptor value on success.

Returns

On success, it returns TTY_OK, otherwise, a TTY_ERROR code.

Author

Wildi Markus

tty_disconnect()

int tty_disconnect

(

int

fd

)

Closes a tty connection and flushes the bus.

Parameters

fd	the file descriptor to close.

Returns

On success, it returns TTY_OK, otherwise, a TTY_ERROR code.

tty_error_msg()

void tty_error_msg	(	int	err_code,
		char *	err_msg,
		int	err_msg_len
	)

Retrieve the tty error message.

Parameters

err_code	the error code return by any TTY function.
err_msg	an initialized buffer to hold the error message.
err_msg_len	length in bytes of err_msg

tty_nread_section()

int tty_nread_section	(	int	fd,
		char *	buf,
		int	nsize,
		char	stop_char,
		int	timeout,
		int *	nbytes_read
	)

read buffer from terminal with a delimiter

Parameters

fd	file descriptor
buf	pointer to store data. Must be initilized and big enough to hold data.
stop_char	if the function encounters stop_char then it stops reading and returns the buffer.
nsize	size of buf. If stop character is not encountered before nsize, the function aborts.
timeout	number of seconds to wait for terminal before a timeout error is issued.
nbytes_read	the number of bytes read.

Returns

On success, it returns TTY_OK, otherwise, a TTY_ERROR code.

tty_read()

int tty_read	(	int	fd,
		char *	buf,
		int	nbytes,
		int	timeout,
		int *	nbytes_read
	)

read buffer from terminal

Parameters

fd	file descriptor
buf	pointer to store data. Must be initilized and big enough to hold data.
nbytes	number of bytes to read.
timeout	number of seconds to wait for terminal before a timeout error is issued.
nbytes_read	the number of bytes read.

Returns

On success, it returns TTY_OK, otherwise, a TTY_ERROR code.

tty_read_section()

int tty_read_section	(	int	fd,
		char *	buf,
		char	stop_char,
		int	timeout,
		int *	nbytes_read
	)

read buffer from terminal with a delimiter

Parameters

fd	file descriptor
buf	pointer to store data. Must be initilized and big enough to hold data.
stop_char	if the function encounters stop_char then it stops reading and returns the buffer.
timeout	number of seconds to wait for terminal before a timeout error is issued.
nbytes_read	the number of bytes read.

Returns

On success, it returns TTY_OK, otherwise, a TTY_ERROR code.

tty_set_debug()

void tty_set_debug

(

int

debug

)

tty_set_debug Enable or disable debug which prints verbose information.

Parameters

debug

1 to enable, 0 to disable

tty_set_gemini_udp_format()

void tty_set_gemini_udp_format

(

int

enabled

)

tty_timeout()

int tty_timeout	(	int	fd,
		int	timeout
	)

tty_write()

int tty_write	(	int	fd,
		const char *	buffer,
		int	nbytes,
		int *	nbytes_written
	)

Writes a buffer to fd.

Parameters

fd	file descriptor
buffer	a null-terminated buffer to write to fd.
nbytes	number of bytes to write from buffer
nbytes_written	the number of bytes written

Returns

On success, it returns TTY_OK, otherwise, a TTY_ERROR code.

tty_write_string()

int tty_write_string	(	int	fd,
		const char *	buffer,
		int *	nbytes_written
	)

Writes a null terminated string to fd.

Parameters

fd	file descriptor
buffer	the buffer to write to fd.
nbytes_written	the number of bytes written

Returns

On success, it returns TTY_OK, otherwise, a TTY_ERROR code.