title: echo output to a file shows repeated lines
body: <p>I created a Bash Script that is running some commands and It does echo to output information to a file. However, the output file shows double lines for each echo in script. For instance:</p>
  
  <h3>Bash script</h3>
  
  <pre><code>#!/bin/bash
  #VARIAVEIS
  (...)
  LOG=${ANO}-${MES}-${DIA}.HISTORICO.BACKUP.LOG.MYSQL.TXT
  (...)
  DIRTEMP=/root/temp
  (...)
  echo "======================================================"  &gt;&gt;$DIRTEMP/$LOG
  echo "HISTÓRICO BACKUP DO LOG DO MYSQL NO SERVIDOR WEB/SENAC"  &gt;&gt;$DIRTEMP/$LOG
  echo "======================================================"  &gt;&gt;$DIRTEMP/$LOG
  (...)
  </code></pre>
  
  <h3>Output file</h3>
  
  <p><code>/root/temp/${ANO}-${MES}-${DIA}.HISTORICO.BACKUP.LOG.MYSQL.TXT</code></p>
  
  <pre><code>(...)
  ======================================================
  ======================================================
  HISTÓRICO BACKUP DO LOG DO MYSQL NO SERVIDOR WEB/SENAC
  HISTÓRICO BACKUP DO LOG DO MYSQL NO SERVIDOR WEB/SENAC
  ======================================================
  ======================================================
  (...)
  </code></pre>
  
  <p>The script is called from crontab:</p>
  
  <pre><code>55      23      *       *       *       /etc/run.backup.log.mysql &amp; 1&gt; dev/null
  </code></pre>
  
  <p>I don't know what's wrong. Can someone help?</p>