Filter

Filter determines whether a packet satisfies specified condition. Actually Filter is wrapper for bpf_program. For details of filter expression, see tcpdump(1).

Super Class:

Object

Class Methods:

compile(expr, capture[, optimize[, netmask]])

new(expr, capture[, optimize[, netmask]])

Create a new Filter object. expr is a filter string. capture is a Capture object. optimize controls optimization of resulting code. netmask specifies the netmask of the local net.

Created Filter can be applied to packets captured via capture.

If libpcap-0.5 or later used, one of following values can be specified instead of capture:

[snaplen, datalink]

an array containing required parameters

omitted (or nil)

Ethernet default ([68, DLT_EN10MB])

Methods:

self === packet

self =~ packet

Return true if packet matches this filter.

~ self

Return a Filter which represents "not self".

self | other

Return a Filter which represents "self or other".

self & other

Return a Filter which represents "self and other".

source

Returns the orginal string from which the filter is constructed.

fukusima@goto.info.waseda.ac.jp