CTIME(3) CTIME(3)
NAME
ctime, localtime, gmtime, asctime, tm2sec - convert date and
time
SYNOPSIS
#include <u.h>
#include <libc.h>
char* ctime(long clock)
Tm* localtime(long clock)
Tm* gmtime(long clock)
char* asctime(Tm *tm)
long tm2sec(Tm *tm)
DESCRIPTION
Ctime converts a time clock such as returned by time(3) into
ASCII (sic) and returns a pointer to a 30-byte string in the
following form. All the fields have constant width.
Wed Aug 5 01:07:47 EST 1973\n\0
Localtime and gmtime return pointers to structures contain-
ing the broken-down time. Localtime corrects for the time
zone and possible daylight savings time; gmtime converts
directly to GMT. Asctime converts a broken-down time to
ASCII and returns a pointer to a 30-byte string.
typedef
struct {
int sec; /* seconds (range 0..59) */
int min; /* minutes (0..59) */
int hour; /* hours (0..23) */
int mday; /* day of the month (1..31) */
int mon; /* month of the year (0..11) */
int year; /* year A.D. - 1900 */
int wday; /* day of week (0..6, Sunday = 0) */
int yday; /* day of year (0..365) */
char zone[4]; /* time zone name */
int tzoff; /* time zone delta from GMT */
} Tm;
Tm2sec converts a broken-down time to seconds since the
start of the epoch. It ignores wday, and assumes the local
time zone if zone is not GMT.
SOURCE
Page 1 Plan 9 (printed 11/4/25)
CTIME(3) CTIME(3)
/usr/local/plan9/src/lib9/ctime.c
/usr/local/plan9/src/lib9/tm2sec.c
SEE ALSO
date(1), time(3)
BUGS
The return values point to static data whose content is
overwritten by each call.
Daylight Savings Time is ``normal'' in the Southern hemi-
sphere.
These routines are not equipped to handle non-ASCII text,
and are provincial anyway.
To avoid name conflicts with the underlying system, ctime,
localtime, gmtime, asctime, and tm2sec are preprocessor mac-
ros defined as p9ctime, p9localtime, p9gmtime, p9asctime,
and p9tm2sec; see intro(3).
Page 2 Plan 9 (printed 11/4/25)