CFSETOSPEED(3P)

💖 CFSETOSPEED(3P) 💖

okay bestie, welcome to the POSIX Programmer's Manual page for cfsetospeed — yes we're in the 3P girlies section of the man pages, iconic ✨

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🌸 PROLOG 🌸

so like, quick heads up before we dive in: 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. fr fr, check before you ship. 🫶

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✨ NAME ✨

cfsetospeed — set output baud rate 💅

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🎀 SYNOPSIS 🎀

#include <termios.h>

int cfsetospeed(struct termios *termios_p, speed_t speed);

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🦋 DESCRIPTION 🦋

okay so here's the vibe: the cfsetospeed() function shall set the output baud rate stored in the structure pointed to by termios_p to speed. that's it. that's the whole job. queen of doing one thing 🎀

but bestie, important: there shall be no effect on the baud rates set in the hardware until a subsequent successful call to tcsetattr() with the same termios structure. so you're basically writing a note to your future self and tcsetattr() is the one who actually delivers it. 💌

similarly, errors resulting from attempts to set baud rates not supported by the terminal device need not be detected until the tcsetattr() function is called. so like, no gatekeeping at this stage — the error just waits patiently until tcsetattr() shows up. 😭

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💀 RETURN VALUE 💀

• upon successful completion, cfsetospeed() shall return 0 ✅
• otherwise, it shall return -1 and errno may be set to indicate the error ❌

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🚨 ERRORS 🚨

the cfsetospeed() function may fail if:

• EINVAL — the speed value is not a valid baud rate. not it.
• EINVAL — the value of speed is outside the range of possible speed values as specified in <termios.h>. also not it. same error, different crime. 💀

the following sections are informative. yes ma'am, that's the official terminology.

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🌈 EXAMPLES 🌈

None.

(she said "no examples, figure it out" 💀)

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🍓 APPLICATION USAGE 🍓

None.

(also nothing. we're keeping it mysterious 💅)

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👑 RATIONALE 👑

Refer to cfgetispeed().

(that's it. go read your sister's page. sibling energy ✨)

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⭐ FUTURE DIRECTIONS ⭐

None.

(stable queen. no drama on the horizon 🫶)

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💜 SEE ALSO 💜

• cfgetispeed()
• cfgetospeed()
• cfsetispeed()
• tcsetattr()

also, from the Base Definitions volume of POSIX.1‐2017: Chapter 11, General Terminal Interface, <termios.h> 📚

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📜 COPYRIGHT 📜

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 http://www.opengroup.org/unix/online.html .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

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and that's the whole page bestie!! brought to you by IEEE/The Open Group, dated 2017, CFSETOSPEED(3P) era 💖 go set some baud rates, you absolute icon 👑✨