35 lines
1.2 KiB
Scheme
35 lines
1.2 KiB
Scheme
; Use the regular expression module to parse the url
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(use-modules (ice-9 regex) (ice-9 rdelim))
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; Variable to store result
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(define time "")
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; Set the url and parse the hostname, port, and path into variables
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(define url "http://tycho.usno.navy.mil/cgi-bin/timer.pl")
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(define r (make-regexp "^(http://)?([^:/]+)(:)?(([0-9])+)?(/.*)?" regexp/icase))
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(define host (match:substring (regexp-exec r url) 2))
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(define port (match:substring (regexp-exec r url) 4))
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(define path (match:substring (regexp-exec r url) 6))
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; Set port to 80 if it wasn't set above and convert from a string to a number
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(if (eq? port #f) (define port "80"))
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(define port (string->number port))
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; Connect to remote host on specified port
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(let ((s (socket PF_INET SOCK_STREAM 0)))
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(connect s AF_INET (car (hostent:addr-list (gethostbyname host))) port)
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; Send a HTTP request for the specified path
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(display "GET " s)
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(display path s)
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(display " HTTP/1.0\r\n\r\n" s)
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(set! r (make-regexp "<BR>(.+? UTC)"))
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(do ((line (read-line s) (read-line s))) ((eof-object? line))
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(if (regexp-match? (regexp-exec r line))
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(set! time (match:substring (regexp-exec r line) 1)))))
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; Display result
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(display time)
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(newline)
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