CFSETISPEED(3P)

💅 CFSETISPEED — okay so we're setting the input baud rate bestie

hey hi hello welcome to the POSIX Programmer's Manual, specifically the page for cfsetispeed(3P). Pull up a chair, grab a boba, let's talk about serial ports 🫶

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✨ PROLOG ✨

okay so first things first, 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 at all. iykyk 💀

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👑 NAME 👑

cfsetispeed — set input baud rate. that's it. that's the whole job. iconic honestly 🎀

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🦋 SYNOPSIS 🦋

#include <termios.h>

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

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🌸 DESCRIPTION 🌸

So the cfsetispeed() function shall set the input baud rate stored in the structure pointed to by termios_p to speed. very demure, very mindful, it just writes the number into the struct 💖

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 like, this function is just manifesting the change, it's not actually doing it yet bestie ✨

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 no, it won't tell you now. it's giving "we'll find out later" energy 🙈

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🎀 RETURN VALUE 🎀

• Upon successful completion, cfsetispeed() shall return 0 — slay, we ate
• otherwise, -1 shall be returned, and errno may be set to indicate the error — oof, not the vibe 😭

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🔥 ERRORS 🔥

The cfsetispeed() function may fail if:

• EINVAL — The speed value is not a valid baud rate. not a real speed bestie 💀
• EINVAL — The value of speed is outside the range of possible speed values as specified in <termios.h>. out of pocket, out of range, same thing 💅

The following sections are informative.

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🌈 EXAMPLES 🌈

None. — yeah. nothing. no examples. we're on our own fr fr 🫶

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💜 APPLICATION USAGE 💜

None. — also nothing. the void. the silence. mood 😌

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⭐ RATIONALE ⭐

Refer to cfgetispeed(). that's the whole rationale. go read your sibling's page 🧚

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🦄 FUTURE DIRECTIONS 🦄

None. — the future is cancelled apparently ✨

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💖 SEE ALSO 💖

• cfgetispeed()
• cfgetospeed()
• cfsetospeed()
• tcsetattr()

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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anyway that's the page bestie — brought to you by IEEE/The Open Group, dated 2017, from the POSIX Programmer's Manual. go forth and set your input baud rates responsibly 🌟💖✨