

          fmtclock clockval [format] [GMT|{}]
               Converts a Unix integer time value, typically returned
               by getclock, convertclock, or the atime, mtime, or
               ctime options of the file command, to human-readable
               form.  The format argument is a string that describes
               how the date and time are to be formatted.  Field
               descriptors consist of a ``%'' followed by a field
               descriptor character.  All other characters are copied
               into the result.  Valid field descriptors are:

                   %% - Insert a %.
                   %a - Abbreviated weekday name.
                   %A - Full weekday name
                   %b - Abbreviated month name.
                   %B - Full month name.
                   %d - Day of month (01 - 31).
                   %D - Date as %m/%d/%y.
                   %e - Day of month (1-31), no leading zeros.
                   %h - Abbreviated month name.
                   %H - Hour (00 - 23).
                   %I - Hour (00 - 12).
                   %j - Day number of year (001 - 366).
                   %m - Month number (01 - 12).
                   %M - Minute (00 - 59).
                   %n - Insert a new line.
                   %p - AM or PM.
                   %r - Time as %I:%M:%S %p.
                   %R - Time as %H:%M.
                   %S - Seconds (00 - 59).
                   %t - Insert a tab.
                   %T - Time as %H:%M:%S.
                   %U - Week number of year (01 - 52), Sunday is the first
                        day of the week.
                   %w - Weekday number (Sunday = 0).
                   %W - Week number of year (01 - 52), Monday is the first
                        day of the week.
                   %x - Local specific date format.
                   %X - Local specific time format.
                   %y - Year within century (00 - 99).
                   %Y - Year as ccyy (e.g. 1990)
                   %Z - Time zone name.

               If format is not specified, "%a %b %d %H:%M:%S %Z %Y"
               is used.  If GMT is specified, the time will be
               formated as Greenwich Mean Time. If the argument is not
               specified or is empty, then the local timezone will be
               used as defined by the TIMEZONE environment variable.
