stime(2)

💖 stime — set time 💖

okay bestie, so this page is stime(2), straight out of the System Calls Manual, and it's literally the Unix syscall that sets the whole system's clock. it's giving legacy, and ngl we're gonna talk about why in a sec. ✨

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🌸 NAME 🌸

stime — set time 🕰️

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🎀 SYNOPSIS 🎀

#include <time.h>

[[deprecated]] int stime(const time_t *t);

🦋 Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

• stime():
  • Since glibc 2.19:
    • _DEFAULT_SOURCE
  • glibc 2.19 and earlier:
    • _SVID_SOURCE

like, yes, you literally have to define a macro to even see this function, she's that hidden 🙈

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✨ DESCRIPTION ✨

NOTE: This function is deprecated; use clock_settime(2) instead.

okay so heads up: stime() is deprecated, bestie. the modern replacement is clock_settime(2) — go hang out with her instead, she's the main character now 👑

stime() sets the system's idea of the time and date. like, the whole system's. every process, every file timestamp, the vibe of the entire machine. the time, pointed to by t, is measured in seconds since the Epoch, 1970-01-01 00:00:00 +0000 (UTC). so t is just a time_t * pointing at a raw epoch-seconds number. simple. iconic.

and the gatekeeping? immaculate. stime() may be executed only by the superuser. if you're not root, she does not know you. 💅

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🌈 RETURN VALUE 🌈

• on success, zero is returned 🥳
• on error, -1 is returned, and errno is set to indicate the error 😭

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💜 ERRORS 💜

• EFAULT — Error in getting information from user space. (basically you handed her a pointer she could not read from 🙈)
• EPERM — The calling process has insufficient privilege. Under Linux, the CAP_SYS_TIME privilege is required. (you tried to touch the clock without the clock-touching pass, bestie 💀)

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⭐ STANDARDS ⭐

None.

and i oop— she's not in any standard, she's just... there. ungoverned. free-spirited. 🧚

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👑 HISTORY 👑

• SVr4.
• Starting with glibc 2.31, this function is no longer available to newly linked applications and is no longer declared in <time.h>.

so like, if you're compiling something new and you're trying to call her? she's not in the header anymore. she ghosted <time.h> fr fr 💀 the old binaries still work, but new links get nothing. it's giving retirement arc.

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🫶 SEE ALSO 🫶

• date(1)
• settimeofday(2)
• capabilities(7)

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lowkey real talk: if you're reaching for stime() in 2026, please consider clock_settime(2) instead. deprecated is deprecated, no cap. 🔥

this has been your girl walking you through stime(2) from the Linux man-pages 6.20, dated 2026-02-08. stay clocked in, bestie 💖✨