A record is a capture file. It contains several packets captured
  during a sniff. It can also be created by hand. There are 7 formats
  for records: pcap (tcpdump compatible), bin (binary, unreadable by
  humans but fast) and mixed/mixed_wrap/dump/hexa/hexa_wrap (easy to
  read and edit). A record also has an associated DLT (Data Link Type),
  indicating at which level a packet start: raw (start at IP header) and
  ether (start at Ethernet header) are the 2 most common DLT. Tool 13
  displays DLT of each device.
  
  This tool searches a pattern in packets of a record, and saves
  matching packets in another record. The pattern can be a string, a
  mixed ('hello' 09 'bob'), or a regular expression.
  
  Parameter --src-file indicates the input record filename.
  Parameter --dst-file indicates the output record filename.
  Parameter --recordencode defines how to encode data in this record
  (suggested values: bin, pcap and mixed_wrap).
   
  | parameter | description | example | 
| -f|--src-file file | input record file | srcfile.txt | 
| -F|--dst-file file | output record file | dstfile.txt | 
| -r|--recordencode recordencode | encoding type for output record | bin | 
| -p|--pattern data | searched pattern | |
| -c|--case|+c|--no-case | case sensitive | |
| -S|--string|+S|--no-string | search string | This boolean is set. Use + or --no- to unset it. | 
| -M|--mixed|+M|--no-mixed | search mixed string | |
| -R|--regexp|+R|--no-regexp | search regular expression |