timespec(3type)

time in seconds and nanoseconds

distropkg manpages-dev@6.9.1-1dataset 2026-04-01T06:19:02Z+debian+ec4110e+mandoc:1.14.6-4

Synopsis

#include <time.h>
struct timespec {
    time_t     tv_sec;
   /* Seconds */
    /* ... */
  tv_nsec;
  /* Nanoseconds [
0
, 
999'999'999
] */
};

—

NAME

timespec - time in seconds and nanoseconds

SYNOPSIS

bash

#include <time.h>

bash

struct timespec {\n
\n    time_t     tv_sec;\n   /* Seconds */
    /* ... */\n  tv_nsec;\n  /* Nanoseconds [\n0\n, \n999'999'999\n] */
\n};\n

DESCRIPTION

Describes times in seconds and nanoseconds.

tv_nsec is of an implementation-defined signed type capable of holding the specified range. Under glibc, this is usually long, and long long on X32. It can be safely down-cast to any concrete 32-bit integer type for processing.

VERSIONS

Prior to C23, tv_nsec was long.

STANDARDS

C11, POSIX.1-2008.

HISTORY

POSIX.1-2001.

NOTES

The following headers also provide this type: <aio.h>, <mqueue.h>, <sched.h>, <signal.h>, <sys/select.h>, and <sys/stat.h>.