Section: POSIX Programmer's Manual (3P)
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
--- set output baud rate
int cfsetospeed(struct termios *termios_p, speed_t speed);
function shall set the output baud rate stored in the structure pointed
There shall be no effect on the baud rates set in the hardware until a
subsequent successful call to
with the same
structure. Similarly, errors resulting from attempts to set baud rates
not supported by the terminal device need not be detected until the
function is called.
Upon successful completion,
shall return 0; otherwise, it shall return -1 and
may be set to indicate the error.
function may fail if:
value is not a valid baud rate.
The value of
is outside the range of possible speed values as specified in
The following sections are informative.
The Base Definitions volume of POSIX.1-2017,
Chapter 11, General Terminal Interface,
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
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