title: How does °, ± & ² produce ░, ▒ & ▓ in this batch file?
body: <p>This code:</p>
  
  <pre><code>   @echo off
     set /p a=Installing [&lt;nul
     set b=1
     :loop
     if %b% leq 2 set /p a=°&lt;nul
     if %b% gtr 4 if %b% leq 6 set /p a=±&lt;nul
     if %b% gtr 6 if %b% leq 8 set /p a=²&lt;nul
     if %b% gtr 8 if %b% leq 10 set /p a=±&lt;nul
     if %b% gtr 10 set /p a=°&lt;nul
     choice /t 1 /c y /d y&gt;nul
     set /a b=%b%+1
     if %b%==13 (echo ]&amp;goto :eof)
     goto :loop
  </code></pre>
  
  <p>... came from <a href="http://www.experts-exchange.com/OS/Microsoft_Operating_Systems/MS_DOS/A_1237-DOS-ECHO-text-to-previous-line-by-Paul-Tomasi.html#c18182" rel="nofollow">http://www.experts-exchange.com/OS/Microsoft_Operating_Systems/MS_DOS/A_1237-DOS-ECHO-text-to-previous-line-by-Paul-Tomasi.html#c18182</a> and produces the below output in a cmd window:</p>
  
  <pre><code>    Installing [░░▒▒▓▓▒▒░░]
  </code></pre>
  
  <p>However, I cant seem to find an explanation through google as to how this works. Substituting other extended ascii characters into their place seems to produce "The syntax of the command is incorrect", so have only managed to guess that this is a hack whereby something exchanges these characters to lower characters in the extended ascii set, by way of unintended-by-the-designers trick.</p>
  
  <p>If anyone could also suggest a good website for learning more about cmd / cmd programs' features like this, it would be appreciated.</p>