GMTIME(3) Library Functions Manual GMTIME(3)

gmtime gmtime_r — convert a time value to a broken-down UTC time

#include <time.h>

struct tm *gmtime(const time_t *timer);
struct tm *gmtime_r(const time_t *clock, struct tm *result);

The gmtime() function converts the time in seconds since the Epoch pointed to by timer into a broken-down time, expressed as Coordinated Universal Time (UTC).

The interface need not be reentrant.

The gmtime_r() function converts the calendar time pointed to by into a broken-down time expressed as Coordinated Universal Time (UTC). The broken-down time is stored in the structure referred to by result. The gmtime_r() function also returns the address of the same structure.

The gmtime() function returns a pointer to a struct tm .

Upon successful completion, gmtime_r() returns the address of the structure pointed to by the argument result. If an error is detected, or UTC is not available, gmtime_r() returns a NULL pointer.

No errors are defined.

None.

The asctime(3) , ctime(3) , gmtime() and localtime(3) functions return values in one of two static objects: a broken-down time structure and an array of char . Execution of any of the functions may overwrite the information returned in either of these objects by any of the other functions.

None.

asctime(3) , clock(3) , ctime(3) , difftime(3) , localtime(3) , mktime(3) , strftime(3) , strptime(3) , time(3) , utime(3) , <time.h> .

gmtime() derived from Issue 1 of the SVID.

gmtime_r() derived from the POSIX Threads Extension (1003.1c-1995).

February 1997 posix.fail