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

<tool id="Show beginning1" name="Select first">
  <description>lines from a Query</description>
  <command interpreter="perl">headWrapper.pl $input $lineNum $out_file1</command>
  <inputs>
    <param name="lineNum" size="5" type="integer" value="10" label="Select 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="lineNum" value="10"/>
      <param name="input" value="1.bed"/>
      <output name="out_file1" file="eq-showbeginning.dat"/>
    </test>
  </tests>
  <help>

**What it does**

This tool outputs specified number of lines from the **beginning** of a dataset

-----

**Example**

Selecting 2 lines from this::

    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  +

will produce::

    chr7  56632  56652  D17003_CTCF_R6  310  +
    chr7  56736  56756  D17003_CTCF_R7  354  +

  </help>
</tool>