gawk: Extension Sample Time

 
 16.7.11 Extension Time Functions
 --------------------------------
 
 The 'time' extension adds two functions, named 'gettimeofday()' and
 'sleep()', as follows:
 
 '@load "time"'
      This is how you load the extension.
 
 'the_time = gettimeofday()'
      Return the time in seconds that has elapsed since 1970-01-01 UTC as
      a floating-point value.  If the time is unavailable on this
      platform, return -1 and set 'ERRNO'.  The returned time should have
      sub-second precision, but the actual precision may vary based on
      the platform.  If the standard C 'gettimeofday()' system call is
      available on this platform, then it simply returns the value.
      Otherwise, if on MS-Windows, it tries to use
      'GetSystemTimeAsFileTime()'.
 
 'result = sleep(SECONDS)'
      Attempt to sleep for SECONDS seconds.  If SECONDS is negative, or
      the attempt to sleep fails, return -1 and set 'ERRNO'.  Otherwise,
      return zero after sleeping for the indicated amount of time.  Note
      that SECONDS may be a floating-point (nonintegral) value.
      Implementation details: depending on platform availability, this
      function tries to use 'nanosleep()' or 'select()' to implement the
      delay.