DCMD_CHR_TCFLOW

QNX SDP8.0Devctl and Ioctl CommandsDeveloper

Perform a flow-control operation on a data stream

Synopsis:

#include <sys/dcmd_chr.h>

#define DCMD_CHR_TCFLOW   __DIOT('T', 6, int)   /* TCXONC */

Arguments to devctl():

Argument Value
filedes A file descriptor that you obtained by opening the device.
dcmd DCMD_CHR_TCFLOW
dev_data_ptr A pointer to an int
n_bytes sizeof(int)
dev_info_ptr NULL

Description:

This command performs a flow-control operation on the data stream associated with the file descriptor passed to devctl(). It's also implemented as the TCXONC ioctl() command.

Note:
This command is for internal use, and you shouldn't use it directly. Instead use the tcflow() cover function.

Input:

The action you want to perform (defined in <termios.h>):

TCOOFF
Use software flow control to suspend output on the device associated with the file descriptor.
TCOOFFHW
Use hardware flow control to suspend output on the device associated with the file descriptor.
TCOON
Use software flow control to resume output on the device associated with the file descriptor.
TCOONHW
Use hardware flow control to resume output on the device associated with the file descriptor.
TCIOFF
Cause input to be flow-controlled by sending a STOP character immediately across the communication line associated with the file descriptor, (that is, software flow control).
TCIOFFHW
Cause input to be flow-controlled by using hardware control.
TCION
Resume input by sending a START character immediately across the communication line associated with the file descriptor (that is, software flow control).
TCIONHW
Cause input to be resumed by using hardware flow control.

Output:

None.

See also:

TCXONC

devctl(), tcflow() in the QNX OS C Library Reference

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