Included with Wireshark is a small utility called capinfos, which is a command-line utility to print information about binary capture files.
Example D.2. Help information available from capinfos
$ capinfos -h
Capinfos 1.1.4
Prints information about capture files.
See http://www.wireshark.org for more information.
Usage: capinfos [options] <infile> ...
General:
-t display the capture file type
-E display the capture file encapsulation
Size:
-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)
Time:
-u display the capture duration (in seconds)
-a display the capture start time
-e display the capture end time
Statistic:
-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)
Miscellaneous:
-h display this help and exit
If no options are given the default is to display all infos