& convtime()
 
  Syntax: convtime(<time string>)
 
  This functions converts a time string to the number of seconds since 
  Jan 1, 1970. A time string is formatted: Ddd MMM DD HH:MM:SS YYYY 
  where 
 
  Ddd is the day of the week, 
  MMM is the month, DD is the day of the month, 
  HH is the hour in 24-hour time, 
  MM is the minutes, SS is the seconds, and 
  YYYY is the year. 
  
  If you supply an incorrectly formatted string, it will return -1.
 
  Note: This function may also be called as time2secs().
 
  Example:
 
  > say time()
  You say "Wed Jun 24 10:22:54 1992"
  > say convtime(Wed Jun 24 10:22:54 1992)
  You say "709395774"
 
  See Also: convsecs(), secs(), time(), starttime().