TCDRAIN(3C) Standard C Library Functions TCDRAIN(3C)
tcdrain - wait for transmission of output
#include <termios.h>
int tcdrain(int fildes);
The tcdrain() function waits until all output written to the object
referred to by fildes is transmitted. The fildes argument is an open
file descriptor associated with a terminal.
Any attempts to use tcdrain() from a process which is a member of a
background process group on a fildes associated with its controlling
terminal, will cause the process group to be sent a SIGTTOU signal.
If the calling process is blocking or ignoring SIGTTOU signals, the
process is allowed to perform the operation, and no signal is sent.
Upon successful completion, 0 is returned. Otherwise, -1 is returned
and errno is set to indicate the error.
The tcdrain() function will fail if:
EBADF
The fildes argument is not a valid file descriptor.
EINTR
A signal interrupted tcdrain().
ENOTTY
The file associated with fildes is not a terminal.
The tcdrain() function may fail if:
EIO
The process group of the writing process is orphaned, and the
writing process is not ignoring or blocking SIGTTOU.
See attributes(7) for descriptions of the following attributes:
+--------------------+--------------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+--------------------------------+
|Interface Stability | Standard |
+--------------------+--------------------------------+
|MT-Level | MT-Safe, and Async-Signal-Safe |
+--------------------+--------------------------------+
tcflush(3C), termio(4I), attributes(7), standards(7)
August 14, 2002 TCDRAIN(3C)
NAME
tcdrain - wait for transmission of output
SYNOPSIS
#include <termios.h>
int tcdrain(int fildes);
DESCRIPTION
The tcdrain() function waits until all output written to the object
referred to by fildes is transmitted. The fildes argument is an open
file descriptor associated with a terminal.
Any attempts to use tcdrain() from a process which is a member of a
background process group on a fildes associated with its controlling
terminal, will cause the process group to be sent a SIGTTOU signal.
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, 0 is returned. Otherwise, -1 is returned
and errno is set to indicate the error.
ERRORS
The tcdrain() function will fail if:
EBADF
The fildes argument is not a valid file descriptor.
EINTR
A signal interrupted tcdrain().
ENOTTY
The file associated with fildes is not a terminal.
The tcdrain() function may fail if:
EIO
The process group of the writing process is orphaned, and the
writing process is not ignoring or blocking SIGTTOU.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+--------------------+--------------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+--------------------------------+
|Interface Stability | Standard |
+--------------------+--------------------------------+
|MT-Level | MT-Safe, and Async-Signal-Safe |
+--------------------+--------------------------------+
SEE ALSO
tcflush(3C), termio(4I), attributes(7), standards(7)
August 14, 2002 TCDRAIN(3C)