adjtime(3) Library Functions Manual adjtime(3) adjtime - (libc -lc) #include int adjtime(const struct timeval *delta, struct timeval *olddelta); glibc ( feature_test_macros(7)): adjtime(): glibc 2.19: _DEFAULT_SOURCE glibc 2.19 : _BSD_SOURCE adjtime() ( gettimeofday(2)). delta. : struct timeval { time_t tv_sec; /* */ suseconds_t tv_usec; /* */ }; delta ( ) . delta . adjtime() adjtime() delta NULL . olddelta NULL . adjtime() 0. -1 errno . EINVAL delta . EPERM . CAP_SYS_TIME. attributes(7). +------------+------------------------------------+--------------------+ || | | +------------+------------------------------------+--------------------+ |adjtime() | | MT-Safe | +------------+------------------------------------+--------------------+ . 4.3BSD System V. adjtime() . adjtime() ( make(1)). adjtime() . delta. glibc delta (INT_MAX / 1000000 - 2) (INT_MIN / 1000000 + 2) (2145 -2145 i386 ). delta NULL olddelta. ( adjtime() .) glibc 2.8 2.6.26 . adjtimex(2), gettimeofday(2), time(7) 3 . . : . 6.18 8 2026 adjtime(3)