title: awk does not read from pipe
body: <p>I'm new to awk and shell script. 
  When I execute this command:</p>
  
  <pre><code>~$ sudo cat /dev/ttyUSB0
  </code></pre>
  
  <p>It prints:</p>
  
  <pre><code>SOFTPAY:F:isoutl.c|L:01301|(
  SOFTPAY:F:isoutl.c|L:01307|600020000008002018010000800000920000121947070700203231313030323832
  SOFTPAY:F:isoutl.c|L:01311|)
  SOFTPAY:F:isoutl.c|L:01301|(
  SOFTPAY:F:isoutl.c|L:01307|600020000008002018010000800000920000121947070700203231313030323832
  SOFTPAY:F:isoutl.c|L:01311|)
  
  SOFTPAY:F:isoutl.c|L:01311|)
  SOFTPAY:F:isoutl.c|L:01307|600000002008102018010002800004920000122009070700203030323131303032383200340032307C6458EE3A4EF4C37D5BEBD6D609A1FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
  SOFTPAY:F:isoutl.c|L:01311|)
  SOFTPAY:F:isoutl.c|L:01301|(
  SOFTPAY:F:isoutl.c|L:01307|600000002008102018010002800004920000122009070700203030323131303032383200340032307C6458EE3A4EF4C37D5BEBD6D609A1FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
  SOFTPAY:F:isoutl.c|L:01311|)
  </code></pre>
  
  <p>When I execute:</p>
  
  <pre><code>~$ sudo cat /dev/ttyUSB0 | grep --line-buffered "SOFTPAY:F:isoutl.c|L:01307|"
  </code></pre>
  
  <p>It prints:</p>
  
  <pre><code>SOFTPAY:F:isoutl.c|L:01307|600020000008002018010000800000920000121546070700203231313030323832
  SOFTPAY:F:isoutl.c|L:01307|600020000008002018010000800000920000121546070700203231313030323832
  SOFTPAY:F:isoutl.c|L:01307|600000002008102018010002800004920000121603070700203030323131303032383200340032AE66FF30893AD0E4ABF1E6F6C17F229AFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
  SOFTPAY:F:isoutl.c|L:01307|600000002008102018010002800004920000121603070700203030323131303032383200340032AE66FF30893AD0E4ABF1E6F6C17F229AFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
  </code></pre>
  
  <p>When I type:</p>
  
  <pre><code>~$ sudo cat /dev/ttyUSB0 | grep --line-buffered "SOFTPAY:F:isoutl.c|L:01307|" | uniq
  </code></pre>
  
  <p>It prints out:</p>
  
  <pre><code>SOFTPAY:F:isoutl.c|L:01307|600020000008002018010000800000920000104334070700203231313030323832
  SOFTPAY:F:isoutl.c|L:01307|60000000200810201801000280000492000010435107070020303032313130303238320034003228D4F55F51CBFF1D673D037DBBE5BADCFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
  </code></pre>
  
  <p>But when I execute: </p>
  
  <pre><code>~$ sudo cat /dev/ttyUSB0 | grep --line-buffered "SOFTPAY:F:isoutl.c|L:01307|" | uniq | awk ' {FS="|"; print $3;}' 
  </code></pre>
  
  <p>It prints nothing.</p>