gawk: Extension Sample Time

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