root/galaxy-central/tools/filters/remove_beginning.xml

<tool id="Remove beginning1" name="Remove beginning">
  <description>of a file</description>
  <command interpreter="perl">remove_beginning.pl $input $num_lines $out_file1</command>
  <inputs>
    <param name="num_lines" size="5" type="integer" value="1" label="Remove first" help="lines"/>
    <param format="txt" name="input" type="data" label="from"/>
  </inputs>
  <outputs>
    <data format="input" name="out_file1" metadata_source="input"/>
  </outputs>
  <tests>
    <test>
      <param name="num_lines" value="5"/>
      <param name="input" value="1.bed"/>
      <output name="out_file1" file="eq-removebeginning.dat"/>
    </test>
  </tests>
  <help>

**What it does**

This tool removes a specified number of lines from the beginning of a dataset.

-----

**Example**

Input File::

    chr7  56632  56652   D17003_CTCF_R6  310  +
    chr7  56736  56756   D17003_CTCF_R7  354  +
    chr7  56761  56781   D17003_CTCF_R4  220  +
    chr7  56772  56792   D17003_CTCF_R7  372  +
    chr7  56775  56795   D17003_CTCF_R4  207  +

After removing the first 3 lines the dataset will look like this::

    chr7  56772  56792   D17003_CTCF_R7  372  +
    chr7  56775  56795   D17003_CTCF_R4  207  +

</help>
</tool>