CFSETISPEED(3POSIX)

💖 cfsetispeed — POSIX Programmer's Manual, bestie edition 💖

Hiii okay so welcome to CFSETISPEED(3POSIX), straight outta the POSIX Programmer's Manual ✨ This whole page is part of that manual, and before we go any further there's a lil disclaimer you gotta hear: the Linux implementation of this interface may differ — so consult the corresponding Linux manual page for the details of Linux behavior — or, plot twist, the interface may not even be implemented on Linux. So do your vibe check first, k? 🫶

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🎀 NAME

cfsetispeed — set input baud rate 💅

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🌸 SYNOPSIS

#include <termios.h>

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

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✨ DESCRIPTION

Okay so here's the tea. cfsetispeed() shall set the input baud rate stored in the structure pointed to by termios_p to speed. That's it, that's the job. 🎯

But bestie, listen — 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 this function is like, lowkey just writing a note for later. The hardware doesn't hear about it yet. 🙈

And similarly (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 don't come for cfsetispeed() when the error shows up late. It's not its fault, fr fr. 😭

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🔥 RETURN VALUE

Upon successful completion, cfsetispeed() shall return 0 🎉

Otherwise, -1 shall be returned, and errno may be set to indicate the error. So yeah, negative one is the "it's giving error" number. 💀

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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, babes. 🚫
• EINVAL — the value of speed is outside the range of possible speed values as specified in <termios.h>. Like, you went too far. Out of bounds. Beyond the chart. 📉

The following sections are informative. 👀

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🍓 EXAMPLES

None. 😌 (Iconic of it to simply not.)

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🦋 APPLICATION USAGE

None. 🧚 (Also iconic.)

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🧚 RATIONALE

Refer to cfgetispeed(). That's the whole thing. Go read your other bestie. 🫶

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🌈 FUTURE DIRECTIONS

None. ✨ (The future is bright and also empty, 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 .

Okay that's the legal bit, and yes you have to read it, no skipping, it's literally the rules 💅

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And that's the whole page, bestie!! Brought to you by IEEE/The Open Group, 2017, filed under CFSETISPEED(3POSIX). Go set some input baud rates, you absolute main character. 🎀✨🦋