tcflow(3)tcflow(3)NAMEtcflow - Perform flow control functions
SYNOPSIS
#include <termios.h>
int tcflow(
int filedes,
int action );
LIBRARY
Standard C Library (libc)
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
tcflow(): XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
PARAMETERS
Specifies an open file descriptor. Specifies one of the following:
Suspend output. Restart suspended output. Transmit a STOP character,
which is intended to cause the terminal device to stop transmitting
data to the system. Transmit a START character, which is intended to
cause the terminal device to start transmitting data to the system.
DESCRIPTION
The tcflow() function suspends transmission or reception of data on the
object referred to by the filedes parameter, depending on the value of
the action parameter.
A process group is sent a SIGTTOU signal if the tcflow() function is
called from one of its member processes. If the calling process is
blocking or ignoring SIGTTOU signals, the process is allowed to perform
the operation and no signal is sent.
RETURN VALUES
Upon successful completion, a value of 0 (zero) is returned. Otherwise,
a value of -1 is returned and errno is set to indicate the error.
ERRORS
The tcflow() function sets errno to the specified values for the fol‐
lowing conditions:
The filedes parameter does not specify a valid file descriptor. The
action parameter is not a supported value. The file associated with
the filedes parameter is not a terminal.
SEE ALSO
Functions: tcdrain(3), tcflush(3), tcsendbreak(3)
Files: termios(4)
Standards: standards(5)tcflow(3)
