Synopsis
#include <termios.h>
int tcflush(int fildes, int queue_selector);
Status
Partially implemented
Conformance
IEEE Std 1003.1-2017
Description
tcflush() - flush non-transmitted output data, non-read input data, or both
Upon successful completion, tcflush() shall discard data written to the object referred to by fildes (an open file
descriptor associated with a terminal) but not transmitted, or data received but not read, depending on the value of
queue_selector:
-
If queue_selector is
TCIFLUSH, it shall flush data received but not read. -
If queue_selector is
TCOFLUSH, it shall flush data written but not transmitted. -
If queue_selector is
TCIOFLUSH, it shall flush both data received but not read and data written but not transmitted.
Attempts to use tcflush() from a process which is a member of a background process group on a fildes associated
with its controlling terminal shall cause the process group to be sent a SIGTTOU signal. If the calling thread is
blocking SIGTTOU signals or the process is ignoring SIGTTOU signals, the process shall be allowed to perform the
operation, and no signal is sent.
Return value
Upon successful completion, 0 shall be returned. Otherwise, -1 shall be returned and errno set to indicate the
error.
Errors
The tcflush() function shall fail if:
-
EBADF- The fildes argument is not a valid file descriptor. -
EINVAL- The queue_selector argument is not a supported value. -
EIO- The process group of the writing process is orphaned, the calling thread is not blocking SIGTTOU, and the process is not ignoring SIGTTOU. -
ENOTTY- The file associated with fildes is not a terminal.
Tests
Untested
Known bugs
None