expand_number(3bsd)

💖 expand_number — the 3bsd page, but make it cute 💖

okay bestie, so this is expand_number(3bsd), aka the libbsd girlie who takes your lil human-readable number string and turns it into a real actual number. she's from the 3bsd manual section, she's serving utility, she's iconic, let's go 🫶

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✨ NAME ✨

expand_number — format a number from human readable form

yes that's the whole vibe. un-formatting. reverse-formatting. taking the cute lil 1K you wrote and making it a whole real integer. the way that she does that 💅

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📚 LIBRARY 📚

Utility functions from BSD systems (libbsd, -lbsd)

so like, she lives in libbsd, and when you're linking you hit her with -lbsd. no cap.

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🌸 SYNOPSIS 🌸

#include <libutil.h>

(See libbsd(7) for include usage.)

int
expand_number(const char *buf, uint64_t *num);

not me reminding you that you gotta peep libbsd(7) for how the include situation actually works. read it. it's giving necessary. 🙈

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🦋 DESCRIPTION 🦋

The expand_number() function unformats the buf string and stores an unsigned 64-bit quantity at address pointed out by the num argument.

fr fr that's the whole job. you hand her a string, she hands you back a uint64_t at the address num points to. glow up complete ✨

The expand_number() function follows the SI power of two convention.

periodt. SI power of two. not power of ten. remember that, it matters, iykyk.

The prefixes are:

• k — kilo — 1024
• M — mega — 1048576
• G — giga — 1073741824
• T — tera — 1099511627776
• P — peta — 1125899906842624
• E — exa — 1152921504606846976

those are the whole alphabet besties, k through E, no more, no less. memorize them or don't, she'll tell you if you're wrong (see ERRORS, she's dramatic about it 💀)

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👑 RETURN VALUES 👑

Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

so: 0 = slay, -1 = not slay, and errno is the group chat message explaining what went wrong. always check her. she's not gonna text you twice. 💖

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💀 ERRORS 💀

The expand_number() function will fail if:

• [EINVAL] — The given string contains no digits. — like bestie there is literally nothing numeric in here. what am i supposed to do with that. 😭
• [EINVAL] — An unrecognized prefix was given. — you gave her a prefix that is not in the list above. she checked. she's not mad, she's just disappointed.
• [ERANGE] — Result doesn't fit into 64 bits. — you asked for a number so big it cannot exist in a uint64_t. that's not a number, that's a dream. it does not fit. 💀

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🌈 SEE ALSO 🌈

• humanize_number(3bsd) — the other direction. she's the one who makes numbers look cute, expand_number is the one who un-cutes them. they're a duo. main character energy from both of them honestly.

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📜 HISTORY 📜

The expand_number() function first appeared in FreeBSD 6.3.

she's been serving since FreeBSD 6.3 and she has not missed a day since 🎀

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and that's the whole page bestie!! mwah 💋

this lil rewrite is from the Debian crew, dated August 15, 2010 — the expand_number(3bsd) era. take care of her, she's a legacy icon 👑✨