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Web scraping

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Task
Web scraping
You are encouraged to solve this task according to the task description, using any language you may know.
Task

Create a program that downloads the time from this URL:   http://tycho.usno.navy.mil/cgi-bin/timer.pl   and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.


If possible, only use libraries that come at no extra monetary cost with the programming language and that are widely available and popular such as CPAN for Perl or Boost for C++.

8th 

\ Web-scrape sample: get UTC time from the US Naval Observatory:
: read-url \ -- s
 "http://tycho.usno.navy.mil/cgi-bin/timer.pl" net:get 
 not if "Could not connect" throw then 
 >s ;

: get-time
  read-url
  /<BR>.*?(\d{2}:\d{2}:\d{2})\sUTC/   
  tuck r:match if
    1 r:@ . cr
  then ;

get-time bye
Output:
14:08:20

Ada

Library: AWS
with AWS.Client, AWS.Response, AWS.Resources, AWS.Messages;
with Ada.Text_IO, Ada.Strings.Fixed;
use  Ada, AWS, AWS.Resources, AWS.Messages;

procedure Get_UTC_Time is

   Page           : Response.Data;
   File           : Resources.File_Type;
   Buffer         : String (1 .. 1024);
   Position, Last : Natural := 0;
   S              : Messages.Status_Code;
begin
   Page := Client.Get ("http://tycho.usno.navy.mil/cgi-bin/timer.pl");
   S    := Response.Status_Code (Page);
   if S not  in Success then
      Text_IO.Put_Line
        ("Unable to retrieve data => Status Code :" & Image (S) &
         " Reason :" & Reason_Phrase (S));
      return;
   end if;

   Response.Message_Body (Page, File);
   while not End_Of_File (File) loop
      Resources.Get_Line (File, Buffer, Last);
      Position :=
         Strings.Fixed.Index
           (Source  => Buffer (Buffer'First .. Last),
            Pattern => "UTC");
      if Position > 0 then
         Text_IO.Put_Line (Buffer (5 .. Position + 2));
         return;
      end if;
   end loop;
end Get_UTC_Time;

ALGOL 68

Works with: ALGOL 68 version Revision 1 - however grep in string, http content and str error are from a non-standard library
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny
STRING 
   domain="tycho.usno.navy.mil",
   page="cgi-bin/timer.pl";

STRING # search for the needle in the haystack #
   needle = "UTC",
   hay stack = "http://"+domain+"/"+page,

   re success="^HTTP/[0-9.]* 200",
   re result description="^HTTP/[0-9.]* [0-9]+ [a-zA-Z ]*",
   re doctype ="\s\s<![Dd][Oo][Cc][Tt][Yy][Pp][Ee] [^>]+>\s+";

PROC raise error = (STRING msg)VOID: ( put(stand error, (msg, new line)); stop);

PROC is html page = (REF STRING page) BOOL: (
     BOOL out=grep in string(re success, page, NIL, NIL) = 0;
     IF INT start, end;
        grep in string(re result description, page, start, end) = 0
     THEN
        page:=page[end+1:];
        IF grep in string(re doctype, page, start, end) = 0
        THEN page:=page[start+2:]
        ELSE raise error("unknown format retrieving page")
        FI
     ELSE raise error("unknown error retrieving page")
     FI;
     out
);

STRING reply;
INT rc = http content (reply, domain, haystack, 0);
IF rc = 0 AND is html page (reply)
THEN 
  STRING line; FILE freply; associate(freply, reply);
  on logical file end(freply, (REF FILE freply)BOOL: (done; SKIP));
  DO
    get(freply,(line, new line));
    IF string in string(needle, NIL, line) THEN print((line, new line)) FI
  OD;
  done: SKIP
ELSE raise error (strerror (rc))
FI
Output:

Sample 

<BR>Sep. 26, 21:51:17 UTC               Universal Time

App Inventor

App Inventor has a Web component that contains code blocks which simplify Web scraping.
It also has powerful text and list processing language blocks that simplify text scraping.
This is how the code would look if it could be typed:

when ScrapeButton.Click do
  set ScrapeWeb.Url to SourceTextBox.Text
  call ScrapeWeb.Get

when ScrapeWeb.GotText url,responseCode,responseType,responseContent do
  initialize local Left to split at first text (text: get responseContent, at: PreTextBox.Text)
  initialize local Right to "" in
    set Right to select list item (list: get Left, index: 2)
    set ResultLabel.Text to select list item (list: split at first (text:get Right, at: PostTextBox.Text), index: 1)

A picture of the graphical program/

AppleScript

"Alternatively, if the above url is not working, grab the first date/time off this page's talk page." At the time of posting, the first date/time on the talk page is in Michael Mol's invitation to RC's Slack. The code here's aimed specifically at the first date on a page (but can be modified) and doesn't include error handling. 

use AppleScript version "2.4" -- OS X 10.10 (Yosemite) or later
use framework "Foundation"

on firstDateonWebPage(URLText)
    set |⌘| to current application
    set pageURL to |⌘|'s class "NSURL"'s URLWithString:(URLText)
    -- Fetch the page HTML as data.
    -- The Xcode documentation advises against using dataWithContentsOfURL: over a network,
    -- but I'm guessing this applies to downloading large files rather than a Web page's HTML.
    -- If in doubt, the HTML can be fetched as text instead and converted to data in house.
    set HTMLData to |⌘|'s class "NSData"'s dataWithContentsOfURL:(pageURL)
    -- Or:
    (*
    set {HTMLText, encoding} to |⌘|'s class "NSString"'s stringWithContentsOfURL:(pageURL) ¬
        usedEncoding:(reference) |error|:(missing value)
    set HTMLData to HTMLText's dataUsingEncoding:(encoding)
    *)
    
    -- Extract the page's visible text from the HTML.
    set straightText to (|⌘|'s class "NSAttributedString"'s alloc()'s initWithHTML:(HTMLData) ¬
        documentAttributes:(missing value))'s |string|()
    
    -- Use an NSDataDetector to locate the first date in the text. (It's assumed here there'll be one.)
    set dateDetector to |⌘|'s class "NSDataDetector"'s dataDetectorWithTypes:(|⌘|'s NSTextCheckingTypeDate) ¬
        |error|:(missing value)
    set matchRange to dateDetector's rangeOfFirstMatchInString:(straightText) options:(0) ¬
        range:({0, straightText's |length|()})
    
    -- Return the date text found.
    return (straightText's substringWithRange:(matchRange)) as text
end firstDateonWebPage

firstDateonWebPage("https://www.rosettacode.org/wiki/Talk:Web_scraping")
Output:
"20:59, 30 May 2020"

AutoHotkey 

UrlDownloadToFile, http://tycho.usno.navy.mil/cgi-bin/timer.pl, time.html
FileRead, timefile, time.html
pos := InStr(timefile, "UTC")
msgbox % time := SubStr(timefile, pos - 9, 8)

AWK

This is inspired by GETURL example in the manual for gawk. 

#! /usr/bin/awk -f

BEGIN {
  purl = "/inet/tcp/0/tycho.usno.navy.mil/80"
  ORS = RS = "\r\n\r\n"
  print "GET /cgi-bin/timer.pl HTTP/1.0" |& purl
  purl |& getline header
  while ( (purl |& getline ) > 0 )
  {
     split($0, a, "\n")
     for(i=1; i <= length(a); i++)
     {
        if ( a[i] ~ /UTC/ )
        {
          sub(/^<BR>/, "", a[i])
          printf "%s\n", a[i]
        }
     }
  }
  close(purl)
}

BBC BASIC

Works with: BBC BASIC for Windows

Note that the URL cache is cleared so the code works correctly if run more than once. 

      SYS "LoadLibrary", "URLMON.DLL" TO urlmon%
      SYS "GetProcAddress", urlmon%, "URLDownloadToFileA" TO UDTF%
      SYS "LoadLibrary", "WININET.DLL" TO wininet%
      SYS "GetProcAddress", wininet%, "DeleteUrlCacheEntryA" TO DUCE%
      
      url$ = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"
      file$ = @tmp$+"navytime.txt"
      
      SYS DUCE%, url$
      SYS UDTF%, 0, url$, file$, 0, 0 TO result%
      IF result% ERROR 100, "Download failed"
      
      file% = OPENIN(file$)
      REPEAT
        text$ = GET$#file%
        IF INSTR(text$, "UTC") PRINT MID$(text$, 5)
      UNTIL EOF#file%
      CLOSE #file%

C

Works with: POSIX version .1-2001
Library: libcurl

There is no proper error handling. 

#include <stdio.h>
#include <string.h>
#include <curl/curl.h>
#include <sys/types.h>
#include <regex.h>

#define BUFSIZE 16384

size_t lr = 0;

size_t filterit(void *ptr, size_t size, size_t nmemb, void *stream)
{
  if ( (lr + size*nmemb) > BUFSIZE ) return BUFSIZE;
  memcpy(stream+lr, ptr, size*nmemb);
  lr += size*nmemb;
  return size*nmemb;
}

int main()
{
  CURL *curlHandle;
  char buffer[BUFSIZE];
  regmatch_t amatch;
  regex_t cregex;

  curlHandle = curl_easy_init();
  curl_easy_setopt(curlHandle, CURLOPT_URL, "http://tycho.usno.navy.mil/cgi-bin/timer.pl");
  curl_easy_setopt(curlHandle, CURLOPT_FOLLOWLOCATION, 1);
  curl_easy_setopt(curlHandle, CURLOPT_WRITEFUNCTION, filterit);
  curl_easy_setopt(curlHandle, CURLOPT_WRITEDATA, buffer);
  int success = curl_easy_perform(curlHandle);
  curl_easy_cleanup(curlHandle);

  buffer[lr] = 0;
  
  regcomp(&cregex, " UTC", REG_NEWLINE);
  regexec(&cregex, buffer, 1, &amatch, 0);
  int bi = amatch.rm_so;
  while ( bi-- > 0 )
    if ( memcmp(&buffer[bi], "<BR>", 4) == 0 ) break;

  buffer[amatch.rm_eo] = 0;

  printf("%s\n", &buffer[bi+4]);

  regfree(&cregex);
  return 0;
}

C# 

class Program
    {
        static void Main(string[] args)
        {
            WebClient wc = new WebClient();
            Stream myStream = wc.OpenRead("http://tycho.usno.navy.mil/cgi-bin/timer.pl");
            string html = "";
            using (StreamReader sr = new StreamReader(myStream))
            {
                while (sr.Peek() >= 0)
                {
                    html = sr.ReadLine();
                    if (html.Contains("UTC"))
                    {
                        break;
                    }
                }
                
            }
            Console.WriteLine(html.Remove(0, 4));

            Console.ReadLine();
        }
    }

C++

Library: boost
Works with: Visual Studio version 2010 Express Edition with boost-1.46.1 from boostpro.com
Works with: gcc version 4.5.2 with boost-1.46.1, compiled with -lboost_regex -lboost_system -lboost_thread
#include <iostream>
#include <string>
#include <boost/asio.hpp>
#include <boost/regex.hpp>
int main()
{
    boost::asio::ip::tcp::iostream s("tycho.usno.navy.mil", "http");
    if(!s)
        std::cout << "Could not connect to tycho.usno.navy.mil\n";
    s  << "GET /cgi-bin/timer.pl HTTP/1.0\r\n"
       << "Host: tycho.usno.navy.mil\r\n"
       << "Accept: */*\r\n"
       << "Connection: close\r\n\r\n" ;
    for(std::string line; getline(s, line); )
    {
        boost::smatch matches;
        if(regex_search(line, matches, boost::regex("<BR>(.+\\s+UTC)") ) )
        {
            std::cout << matches[1] << '\n';
            break;
        }
    }
}

Caché ObjectScript 

Class Utils.Net [ Abstract ]
{

ClassMethod ExtractHTMLData(pHost As %String = "", pPath As %String = "", pRegEx As %String = "", Output list As %List) As %Status
{
  // implement error handling
  Try {

    // some initialisation
    Set list="", sc=$$$OK
  
    // check input parameters
    If $Match(pHost, "^([a-zA-Z0-9]([a-zA-Z0-9\-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,6}$")=0 {
      Set sc=$$$ERROR($$$GeneralError, "Invalid host name.")
      Quit
    }
    
    // create http request and get page
    Set req=##class(%Net.HttpRequest).%New()
    Set req.Server=pHost
    Do req.Get(pPath)
    
    // check for success
    If $Extract(req.HttpResponse.StatusCode)'=2 {
      Set sc=$$$ERROR($$$GeneralError, "Page not loaded.")
      Quit
    }
    
    // read http response stream
    Set html=req.HttpResponse.Data
    Set html.LineTerminator=$Char(10)
    Set sc=html.Rewind()
    
    // read http response stream
    While 'html.AtEnd {
      Set line=html.ReadLine(, .sc, .eol)
      Set pos=$Locate(line, pRegEx)
      If pos {
        Set parse=$Piece($Extract(line, pos, *), $Char(9))
        Set slot=$ListLength(list)+1
        Set $List(list, slot)=parse
      }
    }
    
  } Catch err {
    
    // an error has occurred
    If err.Name="<REGULAR EXPRESSION>" {
      Set sc=$$$ERROR($$$GeneralError, "Invalid regular expression.")
    } Else {
      Set sc=$$$ERROR($$$CacheError, $ZError)
    }
    
  }
  
  // return status
  Quit sc
}

}
Examples:
USER>Do ##class(Utils.Net).ExtractHTMLData("tycho.usno.navy.mil", "/cgi-bin/timer.pl", "[A-Za-z\.]{3,5} \d{1,2}, \d{1,2}:\d{2}:\d{2} UTC", .list)
USER>Write $List(list)
Mar. 29, 20:45:27 UTC

USER>Do ##class(Utils.Net).ExtractHTMLData("tycho.usno.navy.mil", "/cgi-bin/timer.pl", "[A-Za-z\.]{3,5} \d{1,2}, \d{1,2}:\d{2}:\d{2}", .list)    
USER>Write $ListToString(list, $Char(13,10))                                                                                           
Mar. 29, 20:47:42 UTC
Mar. 29, 04:47:42 PM EDT
Mar. 29, 03:47:42 PM CDT
Mar. 29, 02:47:42 PM MDT
Mar. 29, 01:47:42 PM PDT
Mar. 29, 12:47:42 PM AKDT
Mar. 29, 10:47:42 AM HAST

Ceylon

Don't forget to import ceylon.uri and ceylon.http.client in your module.ceylon file. 

import ceylon.uri {
    parse
}
import ceylon.http.client {
    get
}

shared void run() {

    // apparently the cgi link is deprecated?
    value oldUri = "http://tycho.usno.navy.mil/cgi-bin/timer.pl";
    value newUri = "http://tycho.usno.navy.mil/timer.pl";

    value contents = downloadContents(newUri);
    value time = extractTime(contents);
    print(time else "nothing found");
}

String downloadContents(String uriString) {
    value uri = parse(uriString);
    value request = get(uri);
    value response = request.execute();
    return response.contents;
}

String? extractTime(String contents) =>
        contents
        .lines
        .filter((String element) => element.contains("UTC"))
        .first
        ?.substring(4, 21);

Clojure

Clojure 1.2: 

(second (re-find #" (\d{1,2}:\d{1,2}:\d{1,2}) UTC" (slurp "http://tycho.usno.navy.mil/cgi-bin/timer.pl")))

CoffeeScript

Works with: node.js
http = require 'http'

CONFIG =
  host: 'tycho.usno.navy.mil'
  path: '/cgi-bin/timer.pl'

# Web scraping code tends to be brittle, and this is no exception.
# The tycho time page does not use highly structured markup, so
# we do a real dirty scrape.
scrape_tycho_ust_time = (text) ->
  for line in text.split '\n'
    matches = line.match /(.*:\d\d UTC)/
    if matches
      console.log matches[0].replace '<BR>', ''
      return
  throw Error("unscrapable page!")

# This is low-level-ish code to get data from a URL. It's
# pretty general purpose, so you'd normally tuck this away
# in a library (or use somebody else's library).
wget = (host, path, cb) ->
  options =
    host: host
    path: path
    headers:
      "Cache-Control": "max-age=0"
  
  req = http.request options, (res) ->
    s = ''
    res.on 'data', (chunk) ->
      s += chunk
    res.on 'end', ->
      cb s
  req.end()
 
# Do our web scrape
do -> 
  wget CONFIG.host, CONFIG.path, (data) ->
    scrape_tycho_ust_time data
Output:
> coffee web_scrape.coffee 
Jan. 09, 19:19:07 UTC

Common Lisp

Library: cl-ppcre
Library: DRAKMA
BOA> (let* ((url "http://tycho.usno.navy.mil/cgi-bin/timer.pl")
            (regexp (load-time-value
                     (cl-ppcre:create-scanner "(?m)^.{4}(.+? UTC)")))
            (data (drakma:http-request url)))
       (multiple-value-bind (start end start-regs end-regs)
           (cl-ppcre:scan regexp data)
         (declare (ignore end))
         (when start
           (subseq data (aref start-regs 0) (aref end-regs 0)))))
"Aug. 12, 04:29:51 UTC"

Another Common Lisp solution 

CL-USER> (cl-ppcre:do-matches-as-strings
             (m ".*<BR>(.*)UTC.*"
                (drakma:http-request "http://tycho.usno.navy.mil/cgi-bin/timer.pl"))
           (print (cl-ppcre:regex-replace "<BR>(.*UTC).*" m "\\1")))
"Jul. 13, 06:32:01 UTC"

D 

void main() {
    import std.stdio, std.string, std.net.curl, std.algorithm;

    foreach (line; "http://tycho.usno.navy.mil/cgi-bin/timer.pl".byLine)
        if (line.canFind(" UTC"))
            line[4 .. $].writeln;
}

Delphi

Works with: Delphi 7

There are a number of ways to do this with Delphi using any one of a number of free/open source TCP/IP component suites such as, for example, ICS, Synapse and Indy (which ships with Delphi anyway). However, I thought it would be interesting to do this using the Winsock API direct. 

program WebScrape;

{$APPTYPE CONSOLE}

{.$DEFINE DEBUG}

uses
  Classes,
  Winsock;


{ Function to connect to host, send HTTP request and retrieve response }
function DoHTTPGET(const hostName: PAnsiChar; const resource: PAnsiChar; HTTPResponse: TStrings): Boolean;
const
  Port: integer = 80;
  CRLF = #13#10; // carriage return/line feed
var
  WSAData: TWSAData;
  Sock: TSocket;
  SockAddrIn: TSockAddrIn;
  IPAddress: PHostEnt;
  bytesIn: integer;
  inBuffer: array [0..1023] of char;
  Req: string;
begin
  Result := False;
  HTTPResponse.Clear;

  { Initialise use of the Windows Sockets DLL.
    Older Windows versions support Winsock 1.1 whilst newer Windows
    include Winsock 2 but support 1.1.  Therefore, we'll specify
    version 1.1 ($101) as being the highest version of Windows Sockets
    that we can use to provide greatest flexibility.
    WSAData receives details of the Windows Sockets implementation }
  Winsock.WSAStartUp($101, WSAData);
  try

    { Create a socket for TCP/IP usage passing in
      Address family spec: AF_INET (TCP, UDP, etc.)
      Type specification: SOCK_STREAM
      Protocol: IPPROTO_TCP (TCP) }
    Sock := WinSock.Socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    try

      // Check we have a valid socket
      if (Sock <> INVALID_SOCKET) then
        begin
          // Populate socket address structure
          with SockAddrIn do
            begin
              // Address family specification
              sin_family := AF_INET;
              // Port
              sin_port := htons(Port);
              // Address
              sin_addr.s_addr := inet_addr(hostName);
            end;

          if (SockAddrIn.sin_addr.s_addr = INADDR_NONE) then
            begin
              { As we're using a domain name instead of an
                IP Address, we need to resolve the domain name }
              IPAddress := Winsock.gethostbyname(hostName);

              // Quit if we didn't get an IP Address
              if (IPAddress = nil) then
                Exit;

              // Update the structure with the IP Address
              SockAddrIn.sin_addr.s_addr := PLongint(IPAddress^.h_addr_list^)^;
            end;

          // Try to connect to host
          if (Winsock.connect(Sock, SockAddrIn, SizeOf(SockAddrIn)) <> SOCKET_ERROR) then
            begin
              // OK - Connected

              // Compose our request
              // Each line of the request must be terminated with a carriage return/line feed

              {  The First line specifies method (e.g. GET, POST), path to required resource,
                 and the HTTP version being used.  These three fields are space separated. }
               Req := 'GET '+resource+' HTTP/1.1' + CRLF +

                     // Host: is the only Required header in HTTP 1.1
                     'Host: '+hostName + CRLF +

                     { Persistent connections are the default in HTTP 1.1 but, as we don't want
                       or need one for this exercise, we must include the "Connection: close"
                       header in our request }
                     'Connection: close' + CRLF +
                     
                     CRLF; // Request must end with an empty line!

              // Try to send the request to the host
              if (Winsock.send(Sock,Req[1],Length(Req),0) <> SOCKET_ERROR) then
                begin
                  // Initialise incoming data buffer (i.e. fill array with nulls)
                  FillChar(inBuffer,SizeOf(inBuffer),#0);
                  // Loop until nothing left to read
                  repeat
                    // Read incoming data from socket
                    bytesIn := Winsock.recv(Sock, inBuffer, SizeOf(inBuffer), 0);
                    // Assign buffer to Stringlist
                    HTTPResponse.Text := HTTPResponse.Text + Copy(string(inBuffer),1,bytesIn);
                  until
                    (bytesIn <= 0) or (bytesIn = SOCKET_ERROR);

                  { Our list of response strings should
                    contain at least 1 line }
                  Result := HTTPResponse.Count > 0;
                end;

             end;

        end;

    finally
      // Close our socket
      Winsock.closesocket(Sock);
    end;

  finally
    { This causes our application to deregister itself from this
      Windows Sockets implementation and allows the implementation
      to free any resources allocated on our behalf. }
    Winsock.WSACleanup;
  end;

end;

{ Simple function to locate and return the UTC time from the
  request sent to http://tycho.usno.navy.mil/cgi-bin/timer.pl
  The HTTPResponse parameter contains both the HTTP Headers and
  the HTML served up by the requested resource. }
function ParseResponse(HTTPResponse: TStrings): string;
var
  i: Integer;
begin
  Result := '';

  { Check first line for server response code
    We want something like this: HTTP/1.1 200 OK }
  if Pos('200',HTTPResponse[0]) > 0 then
    begin
      for i := 0 to Pred(HTTPResponse.Count) do
        begin
          { The line we're looking for is something like this:
            <BR>May. 04. 21:55:19 UTC Universal Time }

          // Check each line
          if Pos('UTC',HTTPResponse[i]) > 0 then
            begin
              Result := Copy(HTTPResponse[i],5,Pos('UTC',HTTPResponse[i])-1);
              Break;
            end;

        end;
    end
    else
    Result := 'HTTP Error: '+HTTPResponse[0];
end;


const
  host: PAnsiChar = 'tycho.usno.navy.mil';
  res : PAnsiChar = '/cgi-bin/timer.pl';


var
  Response: TStrings;

begin
  { A TStringList is a TStrings descendant class
    that is used to store and manipulate a list
    of strings.

    Instantiate a stringlist class to
    hold the results of our HTTP GET }
  Response := TStringList.Create;
  try
    // Try an HTTP GET request
    if DoHTTPGET(host,res,Response) then
      begin
        {$IFDEF DEBUG}
        { Write the entire response to
          the console window }
        Writeln(Response.text);
        {$ELSE}
        { Parse the response and write the
          result to the console window }
        Writeln(ParseResponse(Response));
        {$ENDIF DEBUG}
      end
      else
      Writeln('Error retrieving data');

  finally
    Response.Free;
  end;

  // Keep console window open
  Readln;


end.


Example using Indy's IdHTTP component. 

program ReadUTCTime;

{$APPTYPE CONSOLE}

uses SysUtils, Classes, IdHTTP;

var
  s: string;
  lHTTP: TIdHTTP;
  lReader: TStringReader;
begin
  lHTTP := TIdHTTP.Create(nil);
  try
    lReader := TStringReader.Create(lHTTP.Get('http://tycho.usno.navy.mil/cgi-bin/timer.pl'));
    while lReader.Peek > 0 do
    begin
      s := lReader.ReadLine;
      if Pos('UTC', s) > 0 then
      begin
        Writeln(s);
        Break;
      end;
    end;
  finally
    lHTTP.Free;
    lReader.Free;
  end;
end.

E 

interp.waitAtTop(when (def html := <http://tycho.usno.navy.mil/cgi-bin/timer.pl>.getText()) -> {
    def rx`(?s).*>(@time.*? UTC).*` := html
    println(time)
})

Erlang

Using regular expressions: 

-module(scraping).
-export([main/0]).
-define(Url, "http://tycho.usno.navy.mil/cgi-bin/timer.pl").
-define(Match, "<BR>(.+ UTC)").

main() ->
  inets:start(),
  {ok, {_Status, _Header, HTML}} = httpc:request(?Url),
  {match, [Time]} = re:run(HTML, ?Match, [{capture, all_but_first, binary}]),
  io:format("~s~n",[Time]).

F#

This code is asynchronous - it will not block any threads while it waits on a response from the remote server. 

open System
open System.Net
open System.Text.RegularExpressions

async {
    use wc = new WebClient()
    let! html = wc.AsyncDownloadString(Uri("http://tycho.usno.navy.mil/cgi-bin/timer.pl"))
    return Regex.Match(html, @"<BR>(.+ UTC)").Groups.[1].Value
}
|> Async.RunSynchronously
|> printfn "%s"

Factor 

USING: http.client io sequences ;

"http://tycho.usno.navy.mil/cgi-bin/timer.pl" http-get nip
[ "UTC" swap start [ 9 - ] [ 1 - ] bi ] keep subseq print

Forth

Works with: GNU Forth version 0.7.0
include unix/socket.fs

: extract-time ( addr len type len -- time len )
  dup >r
  search 0= abort" that time not present!"
  dup >r
  begin -1 /string  over 1- c@ [char] > = until       \ seek back to <BR> at start of line
  r> - r> + ;

s" tycho.usno.navy.mil" 80 open-socket
dup s\" GET /cgi-bin/timer.pl HTTP/1.0\n\n" rot write-socket
dup pad 4096 read-socket
s\" \r\n\r\n" search 0= abort" can't find headers!"   \ skip headers
s" UTC" extract-time type cr
close-socket

FunL 

import io.Source

case Source.fromURL( 'http://tycho.usno.navy.mil/cgi-bin/timer.pl', 'UTF-8' ).getLines().find( ('Eastern' in) ) of
  Some( time ) -> println( time.substring(4) )
  None         -> error( 'Easter time not found' )
Output:
Jul. 24, 01:38:23 AM EDT        Eastern Time

Gambas 

Public Sub Main()
Dim sWeb, sTemp, sOutput As String                                          'Variables

Shell "wget -O /tmp/web http://tycho.usno.navy.mil/cgi-bin/timer.pl" Wait   'Use 'wget' to save the web file in /tmp/

sWeb = File.Load("/tmp/web")                                                'Open file and store in sWeb

For Each sTemp In Split(sWeb, gb.NewLine)                                   'Split the file by NewLines..
  If InStr(sTemp, "UTC") Then                                               'If the line contains "UTC" then..
    sOutPut = sTemp                                                         'Extract the line into sOutput
    Break                                                                   'Get out of here
  End If
Next

Print Mid(sOutput, 5)                                                       'Print the result without the '<BR>' tag

End

Output: 

Jun. 10, 15:22:25 UTC           Universal Time

Go 

package main

import (
    "bytes"
    "encoding/xml"
    "fmt"
    "io"
    "net/http"
    "regexp"
    "time"
)

func main() {
    resp, err := http.Get("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
    if err != nil {
        fmt.Println(err) // connection or request fail
        return
    }
    defer resp.Body.Close()
    var us string
    var ux int
    utc := []byte("UTC")
    for p := xml.NewDecoder(resp.Body); ; {
        t, err := p.RawToken()
        switch err {
        case nil:
        case io.EOF:
            fmt.Println("UTC not found")
            return
        default:
            fmt.Println(err) // read or parse fail
            return
        }
        if ub, ok := t.(xml.CharData); ok {
            if ux = bytes.Index(ub, utc); ux != -1 {
                // success: found a line with the string "UTC"
                us = string([]byte(ub))
                break
            }
        }
    }
    // first thing to try: parsing the expected date format
    if t, err := time.Parse("Jan. 2, 15:04:05 UTC", us[:ux+3]); err == nil {
        fmt.Println("parsed UTC:", t.Format("January 2, 15:04:05"))
        return
    }
    // fallback: search for anything looking like a time and print that
    tx := regexp.MustCompile("[0-2]?[0-9]:[0-5][0-9]:[0-6][0-9]")
    if justTime := tx.FindString(us); justTime > "" {
        fmt.Println("found UTC:", justTime)
        return
    }
    // last resort: just print the whole element containing "UTC" and hope
    // there is a human readable time in there somewhere.
    fmt.Println(us)
}
Output:
parsed UTC: May 23, 00:44:13

Groovy 

def time = "unknown"
def text = new URL('http://tycho.usno.navy.mil/cgi-bin/timer.pl').eachLine { line ->
    def matcher = (line =~ "<BR>(.+) UTC")
    if (matcher.find()) {
        time = matcher[0][1]
    }
}
println "UTC Time was '$time'"
Output:
UTC Time was 'Feb. 26, 11:02:30'

Haskell

Using package HTTP-4000.0.8 from HackgageDB 

import Data.List 
import Network.HTTP (simpleHTTP, getResponseBody, getRequest)

tyd = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"

readUTC = simpleHTTP (getRequest tyd)>>=
            fmap ((!!2).head.dropWhile ("UTC"`notElem`).map words.lines). getResponseBody>>=putStrLn

Usage in GHCi: 

*Main> readUTC
08:30:23

Icon and Unicon

Icon

Icon has capability to read web pages using the external function cfunc. The Unicon messaging extensions are more succinct.

Unicon 

procedure main() 
m := open(url := "http://tycho.usno.navy.mil/cgi-bin/timer.pl","m") | stop("Unable to open ",url)
every (p := "") ||:= |read(m)                                                    # read the page into a single string
close(m)

map(p) ? ( tab(find("<br>")), ="<br>", write("UTC time=",p[&pos:find(" utc")]))  # scrape and show
end

J 

   require 'web/gethttp'

   _8{. ' UTC' taketo gethttp 'http://tycho.usno.navy.mil/cgi-bin/timer.pl'
04:32:44

The web/gethttp addon uses Wget on Linux or Windows (J ships with Wget on Windows) and cURL on the Mac.

(A sockets solution is also possible. But, while basic HTTP support is trivial to implement, a full standards compliant implementation and can involve a lot of code to deal with rare corner cases, and the time required to complete a web request is often significantly longer than the time to invoke an external program. This would imply a fair bit of maintenance and testing overhead to deal with issues which rarely matter, if a direct sockets implementation were used.)

Java

The http://tycho.usno.navy.mil/cgi-bin/timer.pl address is no longer available, although the parsing of the text is incredibly simple. 

String scrapeUTC() throws URISyntaxException, IOException {
    String address = "http://tycho.usno.navy.mil/cgi-bin/timer.pl";
    URL url = new URI(address).toURL();
    try (BufferedReader reader = new BufferedReader(new InputStreamReader(url.openStream()))) {
        Pattern pattern = Pattern.compile("^.+? UTC");
        Matcher matcher;
        String line;
        while ((line = reader.readLine()) != null) {
            matcher = pattern.matcher(line);
            if (matcher.find())
                return matcher.group().replaceAll("<.+?>", "");
        }
    }
    return null;
}

I'm using a cached page and get the following output. 

Jun. 25, 17:59:15 UTC


Alternately, using Java 8, with the new web address given in the task description. 

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;

public final class WebScraping {
	
    public static void main(String[] aArgs) {
	    try {
	        URI uri = new URI("https://www.rosettacode.org/wiki/Talk:Web_scraping").parseServerAuthority();	      
	        URL address = uri.toURL();
	        HttpURLConnection connection = (HttpURLConnection) address.openConnection();
	        BufferedReader reader = new BufferedReader( new InputStreamReader(connection.getInputStream()) );
	        
	        final int responseCode = connection.getResponseCode();
	        System.out.println("Response code: " + responseCode);
	        
	        String line;
	        while ( ! ( line = reader.readLine() ).contains("UTC") ) {
	        	/* Empty block */
	        }
	        
	        final int index = line.indexOf("UTC");	        
	        System.out.println(line.substring(index - 16, index + 4));
	        
	        reader.close();
	        connection.disconnect();
	    } catch (IOException ioe) {
	        System.err.println("Error connecting to server: " + ioe.getCause());
	    } catch (URISyntaxException use) {
	    	System.err.println("Unable to connect to URI: " + use.getCause());
		} 
	}
    
}
Output:
Response code: 200
25 August 2022 (UTC)

JavaScript

Due to browser cross-origin restrictions, this script will probably not work in other domains. 

var req = new XMLHttpRequest();
req.onload = function () {
  var re = /[JFMASOND].+ UTC/; //beginning of month name to 'UTC'
  console.log(this.responseText.match(re)[0]);
};
req.open('GET', 'http://tycho.usno.navy.mil/cgi-bin/timer.pl', true);
req.send();

jq

Works with: jq version 1.4

Currently jq does not have built-in curl support, but jq is intended to work seamlessly with other command-line utilities, so we present a simple solution to the problem in the form of a three-line script: 

#!/bin/bash
  curl -Ss 'http://tycho.usno.navy.mil/cgi-bin/timer.pl' |\
    jq -R -r 'if index(" UTC") then .[4:] else empty end'
Output:
$ ./Web_scraping.jq
Apr. 21, 05:19:32 UTC   Universal Time

Julia

I'm using the Requests.jl package for this solution. Note, I used a slightly different URL after finding that the one specified in the task description is deprecated (though it still works). 

using Requests, Printf
 
function getusnotime()
    const url = "http://tycho.usno.navy.mil/timer.pl"
    s = try
        get(url)
        catch err
        @sprintf "get(%s)\n   => %s" url err
    end
    isa(s, Requests.Response) || return (s, false)
    t = match(r"(?<=<BR>)(.*?UTC)", readstring(s))
    isa(t, RegexMatch) || return (@sprintf("raw html:\n %s", readstring(s)), false)
    return (t.match, true)
end
 
(t, issuccess) = getusnotime();
 
if issuccess
    println("The USNO time is ", t)
else
    println("Failed to fetch UNSO time:\n", t)
end
Output:
The USNO time is Apr. 20, 17:54:54 UTC

Checks of Failure Detection

By breaking the USNO URL 

Failed to fetch UNSO time:
get(http://sycho.usno.navy.mil/timer.pl)
   => getaddrinfo callback: unknown node or service (EAI_NONAME)

By breaking the regular expression (using <BR>(.*UTd)) 

Failed to fetch UNSO time:
raw html:
 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final"//EN>
<html>
<body>
<TITLE>What time is it?</TITLE>
<H2> US Naval Observatory Master Clock Time</H2> <H3><PRE>
<BR>Apr. 20, 17:55:31 UTC               Universal Time
<BR>Apr. 20, 01:55:31 PM EDT            Eastern Time
<BR>Apr. 20, 12:55:31 PM CDT            Central Time
<BR>Apr. 20, 11:55:31 AM MDT            Mountain Time
<BR>Apr. 20, 10:55:31 AM PDT            Pacific Time
<BR>Apr. 20, 09:55:31 AM AKDT   Alaska Time
<BR>Apr. 20, 07:55:31 AM HAST   Hawaii-Aleutian Time
</PRE></H3><P><A HREF="http://www.usno.navy.mil"> US Naval Observatory</A>

</body></html>

Kotlin 

// version 1.1.3

import java.net.URL
import java.io.InputStreamReader
import java.util.Scanner
 
fun main(args: Array<String>) {
    val url = URL("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
    val isr = InputStreamReader(url.openStream())
    val sc = Scanner(isr)
    while (sc.hasNextLine()) {
        val line = sc.nextLine()
        if ("UTC" in line) {
            println(line.drop(4).take(17))
            break
        }
    } 
    sc.close()
}

Sample output: 

Aug. 20, 22:38:26

Lasso 

/* have to be used
local(raw_htmlstring = '<TITLE>What time is it?</TITLE>
<H2> US Naval Observatory Master Clock Time</H2> <H3><PRE>
<BR>Jul. 27, 22:57:22 UTC   Universal Time
<BR>Jul. 27, 06:57:22 PM EDT  Eastern Time
<BR>Jul. 27, 05:57:22 PM CDT  Central Time
<BR>Jul. 27, 04:57:22 PM MDT  Mountain Time
<BR>Jul. 27, 03:57:22 PM PDT  Pacific Time
<BR>Jul. 27, 02:57:22 PM AKDT Alaska Time
<BR>Jul. 27, 12:57:22 PM HAST Hawaii-Aleutian Time
</PRE></H3>
')
*/

// should be used
local(raw_htmlstring = string(include_url('http://tycho.usno.navy.mil/cgi-bin/timer.pl')))

local(
  reg_exp = regexp(-find = `<br>(.*?) UTC`, -input = #raw_htmlstring, -ignorecase),
  datepart_txt =  #reg_exp -> find ? #reg_exp -> matchstring(1) | string
)

#datepart_txt
'<br />'
// added bonus showing how parsed string can be converted to date object
local(mydate = date(#datepart_txt, -format = `MMM'.' dd',' HH:mm:ss`))
#mydate -> format(`YYYY-MM-dd HH:mm:ss`)

Result: Jul. 27, 22:57:22

2013-07-27 22:57:22

Liberty BASIC 

if DownloadToFile("http://tycho.usno.navy.mil/cgi-bin/timer.pl", DefaultDir$ + "\timer.htm") = 0 then
        open DefaultDir$ + "\timer.htm" for input as #f
                html$ = lower$(input$(#f, LOF(#f)))
        close #f

        a= instr( html$, "utc" )-1
        print "UTC";mid$( html$, a-9,9)

    end if

end

function DownloadToFile(urlfile$, localfile$)
    open "URLmon" for dll as #url
    calldll #url, "URLDownloadToFileA",_
    0 as long,_         'null
    urlfile$ as ptr,_   'url to download
    localfile$ as ptr,_ 'save file name
    0 as long,_         'reserved, must be 0
    0 as long,_         'callback address, can be 0
    DownloadToFile as ulong  '0=success
    close #url
end function

Because Liberty has to do web operations in ways like this, calling Windows DLLs, there is the Run BASIC variant of LB, in which the task becomes a one-liner.

Lua

Library: LuaSocket

The web page is split on the HTML line break tags. Each line is checked for the required time zone code. Once it is found, we return the instance within that line of three numbers separated by colons - I.E. the time. 

local http = require("socket.http")    -- Debian package is 'lua-socket'

function scrapeTime (pageAddress, timeZone)
    local page = http.request(pageAddress)
    if not page then return "Cannot connect" end
    for line in page:gmatch("[^<BR>]*") do
        if line:match(timeZone) then
            return line:match("%d+:%d+:%d+")
        end
    end
end

local url = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"
print(scrapeTime(url, "UTC"))

The task description states "just the UTC time" but of course we could return the whole line including the zone name and date if required.

M2000 Interpreter 

Module Web_scraping {
	Print "Web scraping"
	function GetTime$(a$, what$="UTC") {
		document a$ ' change string to document
		find a$, what$  ' place data to stack
		Read find_pos
		if find_pos>0 then
			read par_order, par_pos
			b$=paragraph$(a$, par_order)
			k=instr(b$,">")
			if k>0 then if k<par_pos then b$=mid$(b$,k+1) :par_pos-=k
			k=rinstr(b$,"<")
			if k>0 then if k>par_pos then b$=Left(b$,k-1)
			=b$
		end if
	}
	declare msxml2 "MSXML2.XMLHTTP.6.0"
	rem print type$(msxml2)="IXMLHTTPRequest"
	Url$ = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"
	try ok {
		method msxml2, "Open", "GET", url$, false
		method msxml2,"Send"
		with msxml2,"responseText" as txt$
		Print GetTime$(txt$)
	}
	If error or not ok then Print Error$
	declare msxml2 nothing
}
Web_scraping

Maple 

text := URL:-Get("http://tycho.usno.navy.mil/cgi-bin/timer.pl"):
printf(StringTools:-StringSplit(text,"<BR>")[2]);
Output:
May. 16, 20:17:28 UTC		Universal Time

Mathematica /Wolfram Language 

test = StringSplit[Import["http://tycho.usno.navy.mil/cgi-bin/timer.pl"], "\n"];
Extract[test, Flatten@Position[StringFreeQ[test, "UTC"], False]]

MATLAB / Octave 

s  = urlread('http://tycho.usno.navy.mil/cgi-bin/timer.pl');
ix = [findstr(s,'<BR>'), length(s)+1];
for k = 2:length(ix)
     tok = s(ix(k-1)+4:ix(k)-1);
     if findstr(tok,'UTC')
  disp(tok);
     end;
end;

Microsoft Small Basic 

'Entered by AykayayCiti -- Earl L. Montgomery
url_name = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"
url_data = Network.GetWebPageContents(url_name)
find = "UTC"
' the length from the UTC to the time is -18 so we need 
' to subtract from the UTC position
pos = Text.GetIndexOf(url_data,find)-18
result = Text.GetSubText(url_data,pos,(18+3)) 'plus 3 to add the UTC
TextWindow.WriteLine(result)

'you can eleminate a line of code by putting the 
' GetIndexOf insde the GetSubText
'result2 = Text.GetSubText(url_data,Text.GetIndexOf(url_data,find)-18,(18+3))
'TextWindow.WriteLine(result2)
Output:
Mar. 19, 04:19:34 UTC
Press any key to continue...

mIRC Scripting Language 

alias utc {
  sockclose UTC
  sockopen UTC tycho.usno.navy.mil 80
}

on *:SOCKOPEN:UTC: {
  sockwrite -n UTC GET /cgi-bin/timer.pl HTTP/1.1
  sockwrite -n UTC Host: tycho.usno.navy.mil
  sockwrite UTC $crlf
}

on *:SOCKREAD:UTC: {
  sockread %UTC
  while ($sockbr) {
    if (<BR>*Universal Time iswm %UTC) {
      echo -ag $remove(%UTC,<BR>,$chr(9),Universal Time)
      unset %UTC
      sockclose UTC
      return
    }
    sockread %UTC
  }
}

NetRexx 

/* NetRexx */
options replace format comments java crossref symbols binary

parse arg full_short .
if 'FULL'.abbrev(full_short.upper(), 1) then
  dateFull = isTrue()
else
  dateFull = isFalse()
do
  timeURL = java.net.URL('http://tycho.usno.navy.mil/cgi-bin/timer.pl')
  conn = timeURL.openConnection()
  ibr = BufferedReader(InputStreamReader(conn.getInputStream()))
  line = Rexx
  loop label readLoop while ibr.ready()
    line = ibr.readLine()
    if line = null then leave readLoop
    line = line.translate(' ', '\t')
    if line.wordpos('UTC') > 0 then do
      parse line . '>'       udatetime 'UTC' . -
            0    . '>' . ',' utime     'UTC' .
      if dateFull then
        say udatetime.strip() 'UTC'
      else
        say utime.strip()
      leave readLoop
      end
    end readLoop
  ibr.close()
catch ex = IOException
  ex.printStackTrace()
end

method isTrue() public constant returns boolean
  return 1 == 1
method isFalse() public constant returns boolean
  return \isTrue()
Output:
04:29:09

or with an argument that matches 'FULL': 

Jul. 18, 04:29:09 UTC

Nim

Using Rosetta Talk page URL. 

import httpclient, strutils

var client = newHttpClient()

var res: string
for line in client.getContent("https://rosettacode.org/wiki/Talk:Web_scraping").splitLines:
  let k = line.find("UTC")
  if k >= 0:
    res = line[0..(k - 3)]
    let k = res.rfind("</a>")
    res = res[(k + 6)..^1]
    break
echo if res.len > 0: res else: "No date/time found."
Output:
20:59, 30 May 2020

Objeck 

use Net;
use IO;
use Structure;

bundle Default {
  class Scrape {
    function : Main(args : String[]) ~ Nil {
      client := HttpClient->New();
      lines := client->Get("http://tycho.usno.navy.mil/cgi-bin/timer.pl", 80);
      
       i := 0; 
       found := false;
      while(found <> true & i < lines->Size()) {
         line := lines->Get(i)->As(String);
        index := line->Find("UTC");
        if(index > -1) {
          time := line->SubString(index - 9, 9)->Trim();
          time->PrintLine();
          found := true;
        };
        i += 1;
      };
    }
  }
}

OCaml 

let () =
  let _,_, page_content = make_request ~url:Sys.argv.(1) ~kind:GET () in

  let lines = Str.split (Str.regexp "\n") page_content in
  let str =
    List.find
      (fun line ->
        try ignore(Str.search_forward (Str.regexp "UTC") line 0); true
        with Not_found -> false)
      lines
  in
  let str = Str.global_replace (Str.regexp "<BR>") "" str in
  print_endline str;
;;

There are libraries for this, but it's rather interesting to see how to use a socket to achieve this, so see the implementation of the above function make_request on this page.

ooRexx

This uses the RexxcURL wrapper for libcURL As an alternative the supplied rxSock socket library could be used 

/* load the RexxcURL library */
Call RxFuncAdd 'CurlLoadFuncs', 'rexxcurl', 'CurlLoadFuncs'
Call CurlLoadFuncs

url = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"

/* get a curl session */
curl = CurlInit()
if curl \= ''
then do
   call CurlSetopt curl, 'URL', Url
   if curlerror.intcode \= 0 then exit
   call curlSetopt curl, 'OUTSTEM', 'stem.'
   if curlerror.intcode \= 0 then exit
   call CurlPerform curl

   /* content is in a stem - lets get it all in a string */
   content = stem.~allItems~makestring('l')
   /* now parse out utc time */
   parse var content content 'Universal Time' .
   utcTime = content~substr(content~lastpos('<BR>') + 4)
   say utcTime
end

Oz 

declare
  [Regex] = {Module.link ['x-oz://contrib/regex']}

  fun {GetPage Url}
     F = {New Open.file init(url:Url)}
     Contents = {F read(list:$ size:all)}
  in
     {F close}
     Contents
  end

  fun {GetDateString Doc}
     case {Regex.search "<BR>([A-Za-z0-9:., ]+ UTC)" Doc}
     of match(1:S#E ...) then {List.take {List.drop Doc S} E-S+1}
     end
  end

  Url = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"
in
  {System.showInfo {GetDateString {GetPage Url}}}

Peloton

English dialect, short form, using integrated Rexx pattern matcher: 

<@ DEFAREPRS>Rexx Parse</@>
<@ DEFPRSLIT>Rexx Parse|'<BR>' UTCtime 'UTC'</@>
<@ LETVARURL>timer|http://tycho.usno.navy.mil/cgi-bin/timer.pl</@>
<@ ACTRPNPRSVAR>Rexx Parse|timer</@>
<@ SAYVAR>UTCtime</@>

English dialect, padded variable-length form: 

<# DEFINE WORKAREA PARSEVALUES>Rexx Parse</#>
<# DEFINE PARSEVALUES LITERAL>Rexx Parse|'<BR>' UTCtime 'UTC'</#>
<# LET VARIABLE URLSOURCE>timer|http://tycho.usno.navy.mil/cgi-bin/timer.pl</#>
<# ACT REPLACEBYPATTERN PARSEVALUES VARIABLE>Rexx Parse|timer</#>
<# SAY VARIABLE>UTCtime</#>

English dialect, padded short form, using string functions AFT and BEF: 

<@ SAY AFT BEF URL LIT LIT LIT >http://tycho.usno.navy.mil/cgi-bin/timer.pl| UTC|<BR></@>

Perl

Library: LWP
use LWP::Simple;

my $url = 'http://tycho.usno.navy.mil/cgi-bin/timer.pl';
get($url) =~ /<BR>(.+? UTC)/
    and print "$1\n";

Phix

Library: Phix/libcurl
--
-- demo\rosetta\web_scrape.exw
-- ===========================
--
without js -- (libcurl)
include builtins\libcurl.e
include builtins\timedate.e

object res = curl_easy_perform_ex("https://rosettacode.org/wiki/Talk:Web_scraping")
if string(res) then
    res = split(res,'\n')
    for i=1 to length(res) do
      if not match(`<div id="siteNotice">`,res[i]) then -- (24/11/22, exclude notice)
        integer k = match("UTC",res[i])
        if k then
            string line = res[i] -- (debug aid)
            res = line[1..k-3]
            k = rmatch("</a>",res)
            res = trim(res[k+5..$])
            exit
        end if
      end if    
    end for
    ?res
    if string(res) then
        timedate td = parse_date_string(res, {"hh:mm, d Mmmm yyyy"})
        ?format_timedate(td,"Dddd Mmmm ddth yyyy h:mpm")
    end if
else
    ?{"some error",res,curl_easy_strerror(res)}
end if
Output:

(From/as per talk page) 

"20:53, 20 August 2008"
"Wednesday August 20th 2008 8:53pm"

PHP

By iterating over each line: 

<?

$contents = file('http://tycho.usno.navy.mil/cgi-bin/timer.pl');
foreach ($contents as $line){
  if (($pos = strpos($line, ' UTC')) === false) continue;
  echo subStr($line, 4, $pos - 4); //Prints something like "Dec. 06, 16:18:03"
  break;
}

By regular expressions (

Works with: PHP version 4.3.0

): 

<?

echo preg_replace(
  "/^.*<BR>(.*) UTC.*$/su",
  "\\1",
  file_get_contents('http://tycho.usno.navy.mil/cgi-bin/timer.pl')
);

PicoLisp 

(load "@lib/http.l")

(client "tycho.usno.navy.mil" 80 "cgi-bin/timer.pl"
   (when (from "<BR>")
      (pack (trim (till "U"))) ) )
Output:
-> "Feb. 19, 18:11:37"

PowerShell 

$wc = New-Object Net.WebClient
$html = $wc.DownloadString('http://tycho.usno.navy.mil/cgi-bin/timer.pl')
$html -match ', (.*) UTC' | Out-Null
Write-Host $Matches[1]

fyi

.NET provides a property named UtcNow: 

[System.DateTime]::UtcNow
Output:
Wednesday, December 14, 2016 2:06:25 AM

I am currently in the Pacific timezone: 

[System.DateTime]::Now
Output:
Tuesday, December 13, 2016 6:06:25 PM

PureBasic 

URLDownloadToFile_( #Null, "http://tycho.usno.navy.mil/cgi-bin/timer.pl", "timer.htm", 0, #Null)
ReadFile(0, "timer.htm") 
While Not Eof(0)    :    Text$ + ReadString(0)    :    Wend  
MessageRequester("Time", Mid(Text$, FindString(Text$, "UTC", 1) - 9 , 8))

Python 

import urllib
page = urllib.urlopen('http://tycho.usno.navy.mil/cgi-bin/timer.pl')
for line in page:
    if ' UTC' in line:
        print line.strip()[4:]
        break
page.close()
Output:
Aug. 12, 15:22:08 UTC           Universal Time

R

There are two ways of scraping data from webpages. You can either convert the page into an array of strings containing each line of HTML and use regular expressions to locate the useful data, or you can parse the HTML and use xPath to locate them. The first method is quicker for simpler pages, but may become more difficult for more complicated ones.

Regex method

Read the page as lines, find the line containing the string "UTC", then extract the portion of that string that is the date. 

all_lines <- readLines("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
utc_line <- grep("UTC", all_lines, value = TRUE)
matched <- regexpr("(\\w{3}.*UTC)", utc_line)
utc_time_str <- substring(line, matched, matched + attr(matched, "match.length") - 1L)

The last three lines can be made simpler by using

Library: stringr
                   
library(stringr)
utc_line <- all_lines[str_detect(all_lines, "UTC")]
utc_time_str <- str_extract(utc_line, "\\w{3}.*UTC")

Finally, the date and time must be parsed and printed in the desired format. 

       
utc_time <- strptime(utc_time_str, "%b. %d, %H:%M:%S UTC")
strftime(utc_time, "%A, %d %B %Y, %H:%M:%S")

Friday, 13 May 2011, 15:12:20

Parsing method

Library: RCurl
Library: XML

First, retrieve the web page. See HTTP_Request for more options with this. 

library(RCurl)
web_page <- getURL("http://tycho.usno.navy.mil/cgi-bin/timer.pl")

Now parse the html code into a tree and retrieve the pre node that contains interesting bit. Without xPath, the syntax is quite clunky. 

library(XML)
page_tree <- htmlTreeParse(webpage)
times_node <- page_tree$children$html$children$body$children$h3$children$pre$children
times_node <- times_node[names(times_node) == "text"]
time_lines <- sapply(times_node, function(x) x$value)

Here, xPath simplifies things a little bit. 

page_tree <- htmlTreeParse(web_page, useInternalNodes = TRUE)
times_node <- xpathSApply(page_tree, "//pre")[[1]]
times_node <- times_node[names(times_node) == "text"]
time_lines <- sapply(times_node, function(x) as(x, "character"))

Either way, the solution proceeds from here as in the regex method. 

utc_line <- time_lines[str_detect(time_lines, "UTC")]
#etc.

Racket 

#lang racket
(require net/url)
((compose1 car (curry regexp-match #rx"[^ <>][^<>]+ UTC")
           port->string get-pure-port string->url)
 "https://tycho.usno.navy.mil/cgi-bin/timer.pl")

Raku

(formerly Perl 6) 

# 20210301 Updated Raku programming solution

use HTTP::Client; # https://github.com/supernovus/perl6-http-client/

#`[ Site inaccessible since 2019 ?
my $site = "http://tycho.usno.navy.mil/cgi-bin/timer.pl";
HTTP::Client.new.get($site).content.match(/'<BR>'( .+? <ws> UTC )/)[0].say
# ]

my $site = "https://www.utctime.net/";
my $matched = HTTP::Client.new.get($site).content.match(
   /'<td>UTC</td><td>'( .*Z )'</td>'/
)[0];

say $matched;
#$matched = '12321321:412312312 123';
with DateTime.new($matched.Str) {
   say 'The fetch result seems to be of a valid time format.'
} else {
   CATCH { put .^name, ': ', .Str }
}

Note that the string between '<' and '>' refers to regex tokens, so to match a literal '<BR>' you need to quote it, while <ws> refers to the built-in token whitespace. Also, whitespace is ignored by default in Raku regexes.

Output:
｢2021-03-01T17:02:37Z｣
The fetch result seems to be of a valid time format.

REBOL 

REBOL [
  Title: "Web Scraping"
  URL: http://rosettacode.org/wiki/Web_Scraping
]

; Notice that REBOL understands unquoted URL's:

service: http://tycho.usno.navy.mil/cgi-bin/timer.pl

; The 'read' function can read from any data scheme that REBOL knows
; about, which includes web URLs. NOTE: Depending on your security
; settings, REBOL may ask you for permission to contact the service.

html: read service

; I parse the HTML to find the first <br> (note the unquoted HTML tag
; -- REBOL understands those too), then copy the current time from
; there to the "UTC" terminator.

; I have the "to end" in the parse rule so the parse will succeed.
; Not strictly necessary once I've got the time, but good practice.

parse html [thru <br> copy current thru "UTC" to end]

print ["Current UTC time:" current]

Ruby

A verbose example for comparison 

require "open-uri"

open('http://tycho.usno.navy.mil/cgi-bin/timer.pl') do |p|
  p.each_line do |line|
    if line =~ /UTC/
      puts line.match(/ (\d{1,2}:\d{1,2}:\d{1,2}) /)
      break
    end
  end
end

A more concise example 

require 'open-uri'
puts URI.parse('http://tycho.usno.navy.mil/cgi-bin/timer.pl').read.match(/ (\d{1,2}:\d{1,2}:\d{1,2}) UTC/)[1]

Run BASIC 

print word$(word$(httpget$("http://tycho.usno.navy.mil/cgi-bin/timer.pl"),1,"UTC"),2,"<BR>")
Output:
May. 09, 16:13:44

Rust

Translation of: Raku
// 202100302 Rust programming solution

use std::io::Read;
use regex::Regex;

fn main() {

   let client   = reqwest::blocking::Client::new();
   let site     = "https://www.utctime.net/";
   let mut res  = client.get(site).send().unwrap();
   let mut body = String::new();

   res.read_to_string(&mut body).unwrap();

   let re   = Regex::new(r#"<td>UTC</td><td>(.*Z)</td>"#).unwrap();
   let caps = re.captures(&body).unwrap();

   println!("Result : {:?}", caps.get(1).unwrap().as_str());
}
Output:
Result : "2021-03-02T16:27:02Z"

Scala 

import scala.io.Source

object WebTime extends Application {
  val text = Source.fromURL("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
  val utc = text.getLines.find(_.contains("UTC"))
  utc match {
    case Some(s) => println(s.substring(4))
    case _ => println("error")
  }
}

Scheme

Works with: Guile
; Use the regular expression module to parse the url
(use-modules (ice-9 regex) (ice-9 rdelim))

; Variable to store result
(define time "")

; Set the url and parse the hostname, port, and path into variables
(define url "http://tycho.usno.navy.mil/cgi-bin/timer.pl")
(define r (make-regexp "^(http://)?([^:/]+)(:)?(([0-9])+)?(/.*)?" regexp/icase))
(define host (match:substring (regexp-exec r url) 2))
(define port (match:substring (regexp-exec r url) 4))
(define path (match:substring (regexp-exec r url) 6))

; Set port to 80 if it wasn't set above and convert from a string to a number
(if (eq? port #f) (define port "80"))
(define port (string->number port))

; Connect to remote host on specified port
(let ((s (socket PF_INET SOCK_STREAM 0)))
        (connect s AF_INET (car (hostent:addr-list (gethostbyname host))) port)

; Send a HTTP request for the specified path
        (display "GET " s)
        (display path s)
        (display " HTTP/1.0\r\n\r\n" s)

        (set! r (make-regexp "<BR>(.+? UTC)"))
        (do ((line (read-line s) (read-line s))) ((eof-object? line))
                (if (regexp-match? (regexp-exec r line))
                        (set! time (match:substring (regexp-exec r line) 1)))))

; Display result
(display time)
(newline)

Seed7 

$ include "seed7_05.s7i";
  include "gethttp.s7i";

const proc: main is func
  local
    var string: pageWithTime is "";
    var integer: posOfUTC is 0;
    var integer: posOfBR is 0;
    var string: timeStri is "";
  begin
    pageWithTime := getHttp("tycho.usno.navy.mil/cgi-bin/timer.pl");
    posOfUTC := pos(pageWithTime, "UTC");
    if posOfUTC <> 0 then
      posOfBR := rpos(pageWithTime, "<BR>", posOfUTC);
      if posOfBR <> 0 then
        timeStri := pageWithTime[posOfBR + 4 .. pred(posOfUTC)];
        writeln(timeStri);
      end if;
    end if;
  end func;

Sidef 

var ua = frequire('LWP::Simple');
var url = 'http://tycho.usno.navy.mil/cgi-bin/timer.pl';
var match = /<BR>(.+? UTC)/.match(ua.get(url));
say match[0] if match;
Output:
Oct. 27, 00:20:50 UTC

Standard ML

Done in PolyML, needs fetch and sed. Basically the same as the function in PPM_conversion_through_a_pipe#Standard_ML. 

val getTime =  fn url =>
  let
   val fname       = "/tmp/fConv" ^ (String.extract (Time.toString (Posix.ProcEnv.time()),7,NONE) );
   val shellCommand = " fetch -o - \""^ url ^"\" | sed -ne 's/^.*alt=.Los Angeles:\\(.* (Daylight Saving)\\).*$/\\1/p' " ;
    val me         = (  Posix.FileSys.mkfifo
                               (fname,
			        Posix.FileSys.S.flags [ Posix.FileSys.S.irusr,Posix.FileSys.S.iwusr ]
			       ) ; 
                       Posix.Process.fork ()
		     ) 
  in
   if (Option.isSome me) then
     let
        val fin =TextIO.openIn fname
     in
        ( Posix.Process.sleep (Time.fromReal 0.5) ;
          TextIO.inputLine fin  before
	  (TextIO.closeIn fin ; OS.FileSys.remove fname )
	)
     end
   else
     ( OS.Process.system (  shellCommand ^ " > " ^ fname  ^ " 2>&1 "     ) ;                                 
      SOME "" before OS.Process.exit OS.Process.success
     )
end;

print ( valOf (getTime "http://www.time.org"));

output 

11:12 AM (PDT) (Daylight Saving)

Tcl

http and regular expressions

package require http

set request [http::geturl "http://tycho.usno.navy.mil/cgi-bin/timer.pl"]
if {[regexp -line {<BR>(.* UTC)} [http::data $request] --> utc]} {
    puts $utc
}

curl(1) and list operations

Considering the web resource returns tabular data wrapped in a <PRE> tag, you can use Tcl's list processing commands to process its contents. 

set data [exec curl -s http://tycho.usno.navy.mil/cgi-bin/timer.pl]
puts [lrange [lsearch -glob -inline [split $data <BR>] *UTC*] 0 3]

ToffeeScript 

e, page = require('request').get! 'http://tycho.usno.navy.mil/cgi-bin/timer.pl'
l = line for line in page.body.split('\n') when line.indexOf('UTC')>0
console.log l.substr(4,l.length-20)

TUSCRIPT 

$$ MODE TUSCRIPT
SET time = REQUEST ("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
SET utc  = FILTER  (time,":*UTC*:",-)

TXR

Robust

Large amounts of the document are matched (in fact the entire thing!), rather than blindly looking for some small amount of context.

If the web page changes too much, the query will fail to match. TXR will print the word "false" and terminate with a failed exit status. This is preferrable to finding a false positive match and printing a wrong result. (E.g. any random garbage that happened to be in a line of HTML accidentally containing the string UTC). 

@(next @(open-command "wget -c http://tycho.usno.navy.mil/cgi-bin/timer.pl -O - 2> /dev/null"))
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final"//EN>
<html>
<body>
<TITLE>What time is it?</TITLE>
<H2> US Naval Observatory Master Clock Time</H2> <H3><PRE>
@(collect :vars (MO DD HH MM SS (PM "  ") TZ TZNAME))
<BR>@MO. @DD, @HH:@MM:@SS @(maybe)@{PM /PM/} @(end)@TZ@/\t+/@TZNAME
@  (until)
</PRE>@/.*/
@(end)
</PRE></H3><P><A HREF="http://www.usno.navy.mil"> US Naval Observatory</A>

</body></html>
@(output)
@  (repeat)
@MO-@DD @HH:@MM:@SS @PM @TZ
@  (end)
@(end)

Sample run:

$ txr navytime.txr 
Nov-22 22:49:41    UTC
Nov-22 05:49:41 PM EST
Nov-22 04:49:41 PM CST
Nov-22 03:49:41 PM MST
Nov-22 02:49:41 PM PST
Nov-22 01:49:41 PM AKST
Nov-22 12:49:41 PM HAST

Get just the UTC time: 

$ txr -DTZ=UTC navytime.txr 
Nov-22 22:50:16    UTC

Naive

Skip stuff until a line beginning with <BR> has some stuff before "UTC", and capture that stuff: 

@(next @(open-command "wget -c http://tycho.usno.navy.mil/cgi-bin/timer.pl -O - 2> /dev/null"))
@(skip)
<BR>@time@\ UTC@(skip)
@(output)
@time
@(end)

UNIX Shell

This solution uses 'curl' and the standard POSIX command 'sed'. 

#!/bin/sh
curl -s http://tycho.usno.navy.mil/cgi-bin/timer.pl |
   sed -ne 's/^<BR>\(.* UTC\).*$/\1/p'

This solution uses tcsh, wget and awk 

#!/usr/bin/tcsh -f
set page = `wget -q -O- "http://tycho.usno.navy.mil/cgi-bin/timer.pl"`
echo `awk -v s="${page[22]}" 'BEGIN{print substr(s,5,length(s))}'` ${page[23]} ${page[24]}

Ursala

This works by launching the wget command in a separate process and capturing its output. The program is compiled to an executable command. 

#import std
#import cli

#executable ('parameterized','')

whatime =

<.file$[contents: --<''>]>+ -+
   @hm skip/*4+ ~=(9%cOi&)-~l*+ *~ ~&K3/'UTC',
   (ask bash)/0+ -[wget -O - http://tycho.usno.navy.mil/cgi-bin/timer.pl]-!+-

Here is a bash session. 

$ whatime
Jun. 26, 20:49:52 UTC

VBA

Note For this example I altered the VBScript 

Rem add Microsoft VBScript Regular Expression X.X to your Tools References

Function GetUTC() As String
    Url = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"
    With CreateObject("MSXML2.XMLHTTP.6.0")
        .Open "GET", Url, False
        .send
        arrt = Split(.responseText, vbLf)
    End With
    For Each t In arrt
        If InStr(t, "UTC") Then
            GetUTC = StripHttpTags(t)
            
            Exit For
        End If
    Next
End Function
 
Function StripHttpTags(s)
    With New RegExp
        .Global = True
        .Pattern = "\<.+?\>"
        If .Test(s) Then
            StripHttpTags = .Replace(s, "")
        Else
            StripHttpTags = s
        End If
    End With
End Function
 
Sub getTime()
    Rem starting point
    Dim ReturnValue As String
    ReturnValue = GetUTC
    Rem debug.print can be removed
    Debug.Print ReturnValue
    MsgBox (ReturnValue)
End Sub


Output:
Run getTime Subroutine

Mar. 05, 00:57:37 UTC       Universal Time

VBScript 

Function GetUTC() As String
    Url = "http://tycho.usno.navy.mil/cgi-bin/timer.pl"
    With CreateObject("MSXML2.XMLHTTP.6.0")
        .Open "GET", Url, False
        .send
        arrt = Split(.responseText, vbLf)
    End With
    For Each t In arrt
        If InStr(t, "UTC") Then
            GetUTC = StripHttpTags(t)
            
            Exit For
        End If
    Next
End Function
 
Function StripHttpTags(s)
    With New RegExp
        .Global = True
        .Pattern = "\<.+?\>"
        If .Test(s) Then
            StripHttpTags = .Replace(s, "")
        Else
            StripHttpTags = s
        End If
    End With
End Function

WScript.StdOut.Write GetUTC
WScript.StdOut.WriteLine
Output:
Run getTime Subroutine
  
Apr. 21, 21:02:03 UTC          Universal Time

Visual Basic .NET

New, .NET way with StringReader: 

Imports System.Net
Imports System.IO
        Dim client As WebClient = New WebClient()
        Dim content As String = client.DownloadString("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
        Dim sr As New StringReader(content)
        While sr.peek <> -1
            Dim s As String = sr.ReadLine
            If s.Contains("UTC") Then
                Dim time As String() = s.Substring(4).Split(vbTab)
                Console.WriteLine(time(0))
            End If
        End While

Alternative, old fashioned way using VB "Split" function: 

Imports System.Net
        Dim client As WebClient = New WebClient()
        Dim content As String = client.DownloadString("http://tycho.usno.navy.mil/cgi-bin/timer.pl")
        Dim lines() As String = Split(content, vbLf) 'may need vbCrLf 
        For Each line In lines
            If line.Contains("UTC") Then
                Dim time As String() = line.Substring(4).Split(vbTab)
                Console.WriteLine(time(0))
            End If
        Next

V (Vlang) 

import net.http
import net.html

fn main() {
	resp := http.get("https://www.utctime.net") or {println(err) exit(-1)}
	html_doc := html.parse(resp.body)
	utc := html_doc.get_tag("table").str().split("UTC</td><td>")[1].split("</td>")[0]
	rfc_850 := html_doc.get_tag("table").str().split("RFC 850</td><td>")[1].split("</td>")[0]
	println(utc)
	println(rfc_850)
}
Output:
2023-06-06T12:08:01Z
Tuesday, 06-Jun-23 12:08:01 UTC

Wren

Library: libcurl
Library: Wren-pattern

An embedded program so we can ask the C host to download the page for us. This task's talk page is being used for this purpose as the original URL no longer works.

The code is based in part on the C example though, as we don't have regex, we use our Pattern module to identify the first occurrence of a UTC date/time after the site notice. 

/* Web_scraping.wren */

import "./pattern" for Pattern

var CURLOPT_URL = 10002
var CURLOPT_FOLLOWLOCATION = 52
var CURLOPT_WRITEFUNCTION = 20011
var CURLOPT_WRITEDATA = 10001

var BUFSIZE = 16384 * 4

foreign class Buffer {
    construct new(size) {}

    // returns buffer contents as a string
    foreign value
}

foreign class Curl {
    construct easyInit() {}

    foreign easySetOpt(opt, param)

    foreign easyPerform()

    foreign easyCleanup()
}

var buffer = Buffer.new(BUFSIZE)
var curl = Curl.easyInit()
curl.easySetOpt(CURLOPT_URL, "https://rosettacode.org/wiki/Talk:Web_scraping")
curl.easySetOpt(CURLOPT_FOLLOWLOCATION, 1)
curl.easySetOpt(CURLOPT_WRITEFUNCTION, 0) // write function to be supplied by C
curl.easySetOpt(CURLOPT_WRITEDATA, buffer)

curl.easyPerform()
curl.easyCleanup()

var html = buffer.value
var ix = html.indexOf("(UTC)")
ix = html.indexOf("(UTC)", ix + 1) // skip the site notice
if (ix == -1) {
    System.print("UTC time not found.")
    return
}
var p = Pattern.new("/d/d:/d/d, #12/d +1/a =4/d")
var m = p.find(html[(ix - 30).max(0)...ix])
System.print(m.text)


We now embed this in the following C program, compile and run it. 

/* gcc Web_scraping.c -o Web_scraping -lcurl -lwren -lm  */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <curl/curl.h>
#include "wren.h"

/* C <=> Wren interface functions */

char *url, *read_file, *write_file;

size_t bufsize;
size_t lr = 0;

size_t filterit(void *ptr, size_t size, size_t nmemb, void *stream) {
    if ((lr + size*nmemb) > bufsize) return bufsize;
    memcpy(stream+lr, ptr, size * nmemb);
    lr += size * nmemb;
    return size * nmemb;
}

void C_bufferAllocate(WrenVM* vm) {
    bufsize = (int)wrenGetSlotDouble(vm, 1);
    wrenSetSlotNewForeign(vm, 0, 0, bufsize);
}

void C_curlAllocate(WrenVM* vm) {
    CURL** pcurl = (CURL**)wrenSetSlotNewForeign(vm, 0, 0, sizeof(CURL*));
    *pcurl = curl_easy_init();
}

void C_value(WrenVM* vm) {
    const char *s = (const char *)wrenGetSlotForeign(vm, 0);
    wrenSetSlotString(vm, 0, s);
}

void C_easyPerform(WrenVM* vm) {
    CURL* curl = *(CURL**)wrenGetSlotForeign(vm, 0);
    curl_easy_perform(curl);
}

void C_easyCleanup(WrenVM* vm) {
    CURL* curl = *(CURL**)wrenGetSlotForeign(vm, 0);
    curl_easy_cleanup(curl);
}

void C_easySetOpt(WrenVM* vm) {
    CURL* curl = *(CURL**)wrenGetSlotForeign(vm, 0);
    CURLoption opt = (CURLoption)wrenGetSlotDouble(vm, 1);
    if (opt < 10000) {
        long lparam = (long)wrenGetSlotDouble(vm, 2);
        curl_easy_setopt(curl, opt, lparam);
    } else if (opt < 20000) {
        if (opt == CURLOPT_WRITEDATA) {
            char *buffer = (char *)wrenGetSlotForeign(vm, 2);
            curl_easy_setopt(curl, opt, buffer);
        } else if (opt == CURLOPT_URL) {
            const char *url = wrenGetSlotString(vm, 2);
            curl_easy_setopt(curl, opt, url);
        }
    } else if (opt < 30000) {
        if (opt == CURLOPT_WRITEFUNCTION) {
            curl_easy_setopt(curl, opt, &filterit);
        }
    }
}

WrenForeignClassMethods bindForeignClass(WrenVM* vm, const char* module, const char* className) {
    WrenForeignClassMethods methods;
    methods.allocate = NULL;
    methods.finalize = NULL;
    if (strcmp(module, "main") == 0) {
        if (strcmp(className, "Buffer") == 0) {
            methods.allocate = C_bufferAllocate;
        } else if (strcmp(className, "Curl") == 0) {
            methods.allocate = C_curlAllocate;
        }
    }
    return methods;
}

WrenForeignMethodFn bindForeignMethod(
    WrenVM* vm,
    const char* module,
    const char* className,
    bool isStatic,
    const char* signature) {
    if (strcmp(module, "main") == 0) {
        if (strcmp(className, "Buffer") == 0) {
            if (!isStatic && strcmp(signature, "value") == 0)           return C_value;
        } else if (strcmp(className, "Curl") == 0) {
            if (!isStatic && strcmp(signature, "easySetOpt(_,_)") == 0) return C_easySetOpt;
            if (!isStatic && strcmp(signature, "easyPerform()") == 0)   return C_easyPerform;
            if (!isStatic && strcmp(signature, "easyCleanup()") == 0)   return C_easyCleanup;
        }
    }
    return NULL;
}

static void writeFn(WrenVM* vm, const char* text) {
    printf("%s", text);
}

void errorFn(WrenVM* vm, WrenErrorType errorType, const char* module, const int line, const char* msg) {
    switch (errorType) {
        case WREN_ERROR_COMPILE:
            printf("[%s line %d] [Error] %s\n", module, line, msg);
            break;
        case WREN_ERROR_STACK_TRACE:
            printf("[%s line %d] in %s\n", module, line, msg);
            break;
        case WREN_ERROR_RUNTIME:
            printf("[Runtime Error] %s\n", msg);
            break;
    }
}

char *readFile(const char *fileName) {
    FILE *f = fopen(fileName, "r");
    fseek(f, 0, SEEK_END);
    long fsize = ftell(f);
    rewind(f);
    char *script = malloc(fsize + 1);
    fread(script, 1, fsize, f);
    fclose(f);
    script[fsize] = 0;
    return script;
}

static void loadModuleComplete(WrenVM* vm, const char* module, WrenLoadModuleResult result) {
    if( result.source) free((void*)result.source);
}

WrenLoadModuleResult loadModule(WrenVM* vm, const char* name) {
    WrenLoadModuleResult result = {0};
    if (strcmp(name, "random") != 0 && strcmp(name, "meta") != 0) {
        result.onComplete = loadModuleComplete;
        char fullName[strlen(name) + 6];
        strcpy(fullName, name);
        strcat(fullName, ".wren");
        result.source = readFile(fullName);
    }
    return result;
}

int main(int argc, char **argv) {
    WrenConfiguration config;
    wrenInitConfiguration(&config);
    config.writeFn = &writeFn;
    config.errorFn = &errorFn;
    config.bindForeignClassFn = &bindForeignClass;
    config.bindForeignMethodFn = &bindForeignMethod;
    config.loadModuleFn = &loadModule;
    WrenVM* vm = wrenNewVM(&config);
    const char* module = "main";
    const char* fileName = "Web_scraping.wren";
    char *script = readFile(fileName);
    WrenInterpretResult result = wrenInterpret(vm, module, script);
    switch (result) {
        case WREN_RESULT_COMPILE_ERROR:
            printf("Compile Error!\n");
            break;
        case WREN_RESULT_RUNTIME_ERROR:
            printf("Runtime Error!\n");
            break;
        case WREN_RESULT_SUCCESS:
            break;
    }
    wrenFreeVM(vm);
    free(script);
    return 0;
}
Output:
20:53, 20 August 2008

Xidel

http://videlibri.sourceforge.net/xidel.html 

$ xidel -s "https://www.rosettacode.org/wiki/Talk:Web_scraping" -e '
  //p[1]/text()[last()]
'
 20:53, 20 August 2008 (UTC)

$ xidel -s "https://www.rosettacode.org/wiki/Talk:Web_scraping" -e '
  x:parse-dateTime(//p[1]/text()[last()],'hh:nn, dd mmmm yyyy')
'
2008-08-20T20:53:00

$ xidel -s "https://www.rosettacode.org/wiki/Talk:Web_scraping" -e '
  adjust-dateTime-to-timezone(
    x:parse-dateTime(//p[1]/text()[last()],'hh:nn, dd mmmm yyyy'),
    dayTimeDuration('PT0H')
  )
'
$ xidel -s "https://www.rosettacode.org/wiki/Talk:Web_scraping" -e '
  x:parse-dateTime(//p[1]/text()[last()],'hh:nn, dd mmmm yyyy')
  ! adjust-dateTime-to-timezone(.,dayTimeDuration('PT0H'))
'
$ xidel -s "https://www.rosettacode.org/wiki/Talk:Web_scraping" -e '
  x:parse-dateTime(//p[1]/text()[last()],'hh:nn, dd mmmm yyyy')
  => adjust-dateTime-to-timezone(dayTimeDuration('PT0H'))
'
2008-08-20T20:53:00Z

zkl 

const HOST="tycho.usno.navy.mil", PORT=80, dir="/cgi-bin/timer.pl";
get:="GET %s HTTP/1.0\r\nHost: %s:%s\r\n\r\n".fmt(dir,HOST,PORT);
server:=Network.TCPClientSocket.connectTo(HOST,PORT);
server.write(get);       // send request to web serer
data:=server.read(True); // read data from web server

data.seek(data.find("UTC")); // middle of line
c:=data.seek(Void,0);       // start of line
line:=data[c,data.seek(Void,1)-c].text;
line.print(); // the HTML UTC line

re:=RegExp(0'|.*(\d\d:\d\d:\d\d)|);  // get time
re.search(line); 
re.matched[1].println();
Output:
<BR>Mar. 18, 06:18:31 UTC   Universal Time
06:18:31
Retrieved from "https://rosettacode.org/wiki/Web_scraping?oldid=373124"
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