grc/misc_utils/gsm_burst_file_sink.xml

<?xml version="1.0"?>
<block>
  <name>Burst File Sink</name>
  <key>gsm_burst_file_sink</key>
  <import>import grgsm</import>
  <make>grgsm.burst_file_sink($filename)</make>

  <param>
    <name>Destination file</name>
    <key>filename</key>
    <value>/tmp/bursts</value>
    <type>file_open</type>
  </param>

  <sink>
    <name>in</name>
    <type>message</type>
  </sink>
</block>