Included with Wireshark is a small utility called capinfos, which is a command-line utility to print information about binary capture files.
Example D.3. Help information available from capinfos
Capinfos 1.10.0 (SVN Rev 48974 from /trunk-1.10)
Prints various information (infos) about capture files.
See http://www.wireshark.org for more information.
Usage: capinfos [options] <infile> ...
General infos:
-t display the capture file type
-E display the capture file encapsulation
-H display the SHA1, RMD160, and MD5 hashes of the file
-k display the capture comment
Size infos:
-c display the number of packets
-s display the size of the file (in bytes)
-d display the total length of all packets (in bytes)
-l display the packet size limit (snapshot length)
Time infos:
-u display the capture duration (in seconds)
-a display the capture start time
-e display the capture end time
-o display the capture file chronological status (True/False)
-S display start and end times as seconds
Statistic infos:
-y display average data rate (in bytes/sec)
-i display average data rate (in bits/sec)
-z display average packet size (in bytes)
-x display average packet rate (in packets/sec)
Output format:
-L generate long report (default)
-T generate table report
-M display machine-readable values in long reports
Table report options:
-R generate header record (default)
-r do not generate header record
-B separate infos with TAB character (default)
-m separate infos with comma (,) character
-b separate infos with SPACE character
-N do not quote infos (default)
-q quote infos with single quotes (')
-Q quote infos with double quotes (")
Miscellaneous:
-h display this help and exit
-C cancel processing if file open fails (default is to continue)
-A generate all infos (default)
Options are processed from left to right order with later options superceeding
or adding to earlier options.
If no options are given the default is to display all infos in long report
output format.