Q_SETINFO(2const)

✨ Q_SETINFO ✨

okay bestie, buckle up 💖 this is the Q_SETINFO page from the <pink>Linux man-pages 6.20</pink> collection, and it's literally just one little quotactl operation that goes zoom. she's short, she's sweet, she's giving "small but powerful" 💅

It lives in section 2const of the manual, right there next to her sisters ✨

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🌸 NAME 🌸

Q_SETINFO — set information about quotafile 🎀

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📚 LIBRARY 📚

Standard C library (libc, -lc) 🫶

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🦋 SYNOPSIS 🦋

like, here's the whole vibe:

#include <sys/quota.h>

int quotactl(QCMD(Q_SETINFO, type), const char *_Nullable special, 0,
             caddr_t addr);

#include <sys/quota.h>    /* Definition of Q_* constants */
#include <sys/syscall.h>  /* Definition of SYS_* constants */
#include <unistd.h>

int syscall(SYS_quotactl_fd, int fd, QCMD(Q_SETINFO, type), 0,
            struct dqinfo *addr);

notice how the second one is the raw syscall route, SYS_quotactl_fd, because sometimes you gotta go direct to the source, no middleman 😭✨

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💖 DESCRIPTION 💖

Set information about quotafile. that's it. that's the whole job. iconic behaviour honestly 👑

So the addr argument should be a pointer to a dqinfo(2type) structure — yes queen, pointer to struct, we love to see it. And the .dqi_valid field of that dqinfo(2type) structure is the one doing the talking here: it indicates the entries in the structure that have been set by the caller 🎯

⚠️ heads up babes: this operation requires privilege (CAP_SYS_ADMIN). no cap, you literally cannot do this without it, so don't come crying to me 😭

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🔥 RETURN VALUE 🔥

See quotactl(2). ✨

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💀 ERRORS 💀

See quotactl(2). 💀

(yes both of them just point at the parent page, she's lowkey mysterious like that 🙈)

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🌈 STANDARDS 🌈

Linux. 🐧 periodt.

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⭐ HISTORY ⭐

Linux 2.4.22. vintage era, we stan a historically significant queen 🫶

This operation supersedes the Q_SETGRACE and Q_SETFLAGS operations in the previous quota interfaces. so if you were still out here using those old ones... bestie. it's giving legacy. move on 💅

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👑 SEE ALSO 👑

• quotactl(2)
• quotactl_fd(2)
• Q_GETINFO(2const)
• dqinfo(2type)

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aaaand that's the whole page, you ate that 🍓 go forth and set your quota info, main character 💜

mwah 💋 — this lil rewrite came to you courtesy of the Linux man-pages 6.20 release, dated 2026-06-05. xoxo 🎀