TIME(3) BSD Library Functions Manual TIME(3)NAMEtime — get time of day
Standard C Library (libc, -lc)
The time() function returns the value of time in seconds since 0 hours, 0
minutes, 0 seconds, January 1, 1970, Coordinated Universal Time. If an
error occurs, time() returns the value (time_t)-1.
The return value is also stored in *tloc, provided that tloc is non-null.
The time() function may fail for any of the reasons described in
SEE ALSOclock_gettime(2), gettimeofday(2), ctime(3)STANDARDS
The time function conforms to IEEE Std 1003.1-2001 (“POSIX.1”).
A time() function appeared in Version 6 AT&T UNIX.
Neither ISO/IEC 9899:1999 (“ISO C99”) nor IEEE Std 1003.1-2001
(“POSIX.1”) requires time() to set errno on failure; thus, it is impossi‐
ble for an application to distinguish the valid time value -1 (represent‐
ing the last UTC second of 1969) from the error return value.
Systems conforming to earlier versions of the C and POSIX standards
(including older versions of FreeBSD) did not set *tloc in the error
BSD July 18, 2003 BSD