term% ls -F
term% cat index.txt
CTIME(2)                      System Calls Manual                     CTIME(2)

       ctime,  localtime, gmtime, asctime, timezone - convert date and time to

       #include <u.h>
       #include <libc.h>

       char* ctime(long clock)

       Tm*   localtime(long clock)

       Tm*   gmtime(long clock)

       char* asctime(Tm *tm)


       Ctime converts a time clock such as  returned  by  time(2)  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 containing the  bro‐
       ken-down  time.  Localtime corrects for the time zone and possible day‐
       light savings time; gmtime converts directly to GMT.  Asctime  converts
       a broken-down time to ASCII and returns a pointer to a 30-byte string.

              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 */
              } Tm;

       When  local  time is first requested, the program consults the timezone
       environment variable to determine the time zone  and  converts  accord‐
       ingly.   (This  variable  is  set at system boot time by init(8).)  The
       timezone variable contains the normal time zone name and its difference
       from  GMT in seconds followed by an alternate (daylight) time zone name
       and its difference followed by a newline.  The remainder is a  list  of
       pairs of times (seconds past the start of 1970, in the first time zone)
       when the alternate time zone applies.  For example:

              EST -18000 EDT -14400
               9943200 25664400 41392800 57718800 ...

       Greenwich Mean Time is represented by

              GMT 0


       date(1), time(2), init(8)

       The return values point to static data whose content is overwritten  by
       each call.
       Daylight Savings Time is ``normal'' in the Southern hemisphere.
       These  routines are not equipped to handle non-ASCII text, and are pro‐
       vincial anyway.