Move the filter syntax description to the ethereal-filter pod page.

svn path=/trunk/; revision=8701

1 files changed, 1 insertions, 233 deletions

diff --git a/doc/tethereal.pod b/doc/tethereal.pod
index 90dbee07c2..1010569152 100644
--- a/doc/tethereal.pod
+++ b/doc/tethereal.pod
@@ -592,240 +592,8 @@ See manual page of tcpdump(8).
 
 =head1 READ FILTER SYNTAX
 
-Read filters help you remove the noise from a packet trace and let you
-see only the packets that interest you.  If a packet meets the
-requirements expressed in your read filter, then it is printed.  Read
-filters let you compare the fields within a protocol against a specific
-value, compare fields against fields, and to check the existence of
-specified fields or protocols.
-
-The simplest read filter allows you to check for the existence of a
-protocol or field.  If you want to see all packets which contain the IPX
-protocol, the filter would be "ipx".  (Without the quotation marks) To
-see all packets that contain a Token-Ring RIF field, use "tr.rif".
-
-Fields can also be compared against values.  The comparison operators
-can be expressed either through C-like symbols, or through English-like
-abbreviations:
-
-    eq, ==    Equal
-    ne, !=    Not equal
-    gt, >     Greater than
-    lt, <     Less Than
-    ge, >=    Greater than or Equal to
-    le, <=    Less than or Equal to
-
-An additional operator exists that is expressed only in English, not
-punctuation:
-
-    contains  Does the protocol, byte-string, or string contain a value
-
-Furthermore, each protocol field is typed. The types are:
-
-    Unsigned integer (either 8-bit, 16-bit, 24-bit, or 32-bit)
-    Signed integer (either 8-bit, 16-bit, 24-bit, or 32-bit)
-    Boolean
-    Ethernet address (6 bytes)
-    Byte string (n-number of bytes)
-    IPv4 address
-    IPv6 address
-    IPX network number
-    String (text)
-    Double-precision floating point number
-
-An integer may be expressed in decimal, octal, or hexadecimal notation. 
-The following three read filters are equivalent:
-
-    frame.pkt_len > 10
-    frame.pkt_len > 012
-    frame.pkt_len > 0xa
-
-Boolean values are either true or false.  In a read filter expression
-testing the value of a Boolean field, "true" is expressed as 1 or any
-other non-zero value, and "false" is expressed as zero.  For example, a
-token-ring packet's source route field is boolean.  To find any
-source-routed packets, a read filter would be:
-
-    tr.sr == 1
-
-Non source-routed packets can be found with:
-
-    tr.sr == 0
-
-Ethernet addresses, as well as a string of bytes, are represented in hex
-digits.  The hex digits may be separated by colons, periods, or hyphens:
-
-    fddi.dst eq ff:ff:ff:ff:ff:ff
-    ipx.srcnode == 0.0.0.0.0.1
-    eth.src == aa-aa-aa-aa-aa-aa
-
-If a string of bytes contains only one byte, then it is represented as
-an unsigned integer.  That is, if you are testing for hex value 'ff' in
-a one-byte byte-string, you must compare it agains '0xff' and not 'ff'. 
-
-IPv4 addresses can be represented in either dotted decimal notation, or
-by using the hostname:
-
-    ip.dst eq www.mit.edu
-    ip.src == 192.168.1.1
-
-IPv4 addresses can be compared with the same logical relations as numbers:
-eq, ne, gt, ge, lt, and le.  The IPv4 address is stored in host order,
-so you do not have to worry about how the endianness of an IPv4 address
-when using it in a read filter.
-
-Classless InterDomain Routing (CIDR) notation can be used to test if an
-IPv4 address is in a certain subnet.  For example, this display filter
-will find all packets in the 129.111 Class-B network:
-
-    ip.addr == 129.111.0.0/16
-
-Remember, the number after the slash represents the number of bits used
-to represent the network.  CIDR notation can also be used with
-hostnames, in this example of finding IP addresses on the same Class C
-network as 'sneezy':
-
-    ip.addr eq sneezy/24
-
-The CIDR notation can only be used on IP addresses or hostnames, not in
-variable names.  So, a display filter like "ip.src/24 == ip.dst/24" is
-not valid.  (yet)
-
-IPX networks are represented by unsigned 32-bit integers.  Most likely
-you will be using hexadecimal when testing for IPX network values:
-
-    ipx.srcnet == 0xc0a82c00
-
-Strings are enclosed in double-quotes:
-
-    http.request.method == "POST"
-
-Inside double quotes, you may use the backslash to embed a double-quote,
-or an arbitrary byte represented in either octal or hexadecimal.
-
-    browser.comment = "An embedded \" double-quote"
-
-Use of hexadecimal to look for "HEAD":
-
-    http.request.method == "\x48EAD"
-
-Use of octal to look for "HEAD":
-
-    http.request.method == "\x110EAD"
-
-This means that you must escape backslashes with backslashes inside
-double quotes:
-
-    smb.path contains "\\\\SERVER\\SHARE"
-
-to look for \\SERVER\SHARE in "smb.path".
-
-A slice operator also exists.  You can check the substring
-(byte-string) of any protocol or field.  For example, you can filter on
-the vendor portion of an ethernet address (the first three bytes) like
-this:
-
-    eth.src[0:3] == 00:00:83
-
-If the length of your byte-slice is only one byte, then it is still
-represented in hex, but without the preceding "0x": 
-
-    llc[3] == aa
-
-You can use the slice operator on a protocol name, too.  And
-remember, the "frame" protocol encompasses the entire packet, allowing
-you to look at the nth byte of a packet regardless of its frame type
-(Ethernet, token-ring, etc.).
-
-    token[0:5] ne 0.0.0.1.1
-    ipx[0:2] == ff:ff
-    llc[3:1] eq 0xaa
-
-The following syntax governs slices:
-
-	[i:j]	i = start_offset, j = length
-	[i-j]	i = start_offset, j = end_offset, inclusive.
-	[i]	i = start_offset, length = 1
-	[:j]	start_offset = 0, length = j
-	[i:]	start_offset = i, end_offset = end_of_field
-
-Offsets and lengths can be negative, in which case they indicate the
-offset from the B<end> of the field.  Here's how to check the last 4
-bytes of a frame:
-
-    frame[-4:4] == 0.1.2.3
-
-or
-
-    frame[-4:] == 0.1.2.3
-
-You can create complex concatenations of slices using the comma operator:
-
-	field[1,3-5,9:] == 01:03:04:05:09:0a:0b
-
-All the above tests can be combined together with logical expressions. 
-These too are expressable in C-like syntax or with English-like
-abbreviations:
-
-    and, &&   Logical AND
-    or, ||    Logical OR
-    not, !    Logical NOT
-
-Expressions can be grouped by parentheses as well.  The following are
-all valid read filter expression:
-
-    tcp.port == 80 and ip.src == 192.168.2.1
-    not llc
-    (ipx.srcnet == 0xbad && ipx.srnode == 0.0.0.0.0.1) || ip
-    tr.dst[0:3] == 0.6.29 xor tr.src[0:3] == 0.6.29
-
-A special caveat must be given regarding fields that occur more than
-once per packet.  "ip.addr" occurs twice per IP packet, once for the
-source address, and once for the destination address.  Likewise,
-tr.rif.ring fields can occur more than once per packet.  The following
-two expressions are not equivalent:
-
-        ip.addr ne 192.168.4.1
-    not ip.addr eq 192.168.4.1
-
-The first filter says "show me IP packets where an ip.addr exists that
-does not equal 192.168.4.1".  That is, as long as one ip.addr in the
-packet does not equal 192.168.44.1, the packet passes the read
-filter.  The second filter "don't show me any packets that have at least
-one ip.addr field equal to 192.168.4.1".  If one ip.addr is 192.168.4.1,
-the packet does not pass.  If B<neither> ip.addr fields is 192.168.4.1,
-then the packet passes.
-
-It is easy to think of the 'ne' and 'eq' operators as having an implict
-"exists" modifier when dealing with multiply-recurring fields.  "ip.addr
-ne 192.168.4.1" can be thought of as "there exists an ip.addr that does
-not equal 192.168.4.1".
-
-Be careful with multiply-recurring fields; they can be confusing.
-
-Care must also be taken when using the read filter to remove noise
-from the packet trace. If you want to e.g. filter out all IP multicast
-packets to address 224.1.2.3, then using:
-
-    ip.dst ne 224.1.2.3
-
-may be too restrictive. Filtering with "ip.dst" selects only those
-B<IP> packets that satisfy the rule. Any other packets, including all
-non-IP packets, will not be printed. For printing also the non-IP
-packets, you can use one of the following two expressions:
-
-    not ip or ip.dst ne 224.1.2.3
-    not ip.addr eq 224.1.2.3
-
-The first filter uses "not ip" to include all non-IP packets and then
-lets "ip.dst ne 224.1.2.3" to filter out the unwanted IP packets. The
-second filter has already been explained above where filtering with
-multiply occuring fields was discussed.
-
 For a complete table of protocol and protocol fields that are filterable
-in B<Tethereal> see ethereal-filter(4). The abbreviation of the protocol
-or field is given.  This abbreviation is what you use in the read filter.
-The type of the field is also given.
+in B<Tethereal> see ethereal-filter(4).
 
 =head1 FILES