NAME

tcdrain −  Waits for output to complete

LIBRARY

Standard C Library (libc.a)

SYNOPSIS

#include <termios.h>

int tcdrain(
int filedes );

PARAMETERS

filedes Specifies an open file descriptor. 

DESCRIPTION

The tcdrain() function waits until all output written to the object referred to by the filedes parameter has been transmitted. 

A process group is sent a SIGTTOU signal if the tcdrain() 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. 

The tcdrain() function, which suspends the calling process until the request is completed, is redefined so that only the calling thread is suspended. 

NOTES

AES Support Level: Full use

EXAMPLE

To wait until all output has been transmitted, enter:

rc = tcdrain(stdout);

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

If the tcdrain() function fails, errno may be set to one of the following values:

[EBADF] The filedes parameter does not specify a valid file descriptor. 

[EINTR] A signal interrupted the tcdrain() function. 

[ENOTTY] The file associated with the filedes parameter is not a terminal. 

RELATED INFORMATION

Functions: tcflow(3), tcflush(3), tcsendbreak(3)