hf, ef, nf, pf - address to name filters
hf [
-1abcdilN] [
-f format] [
-t secs] [
file
...]
hf -x [
file ...]
ef [
-d] [
file ...]
nf [
-di] [
file ...]
pf [
-d] [
file ...]
These filters reads the named files (or from stdin if there are none) and
replace occurrences of a particular kind of address to the corresponding name:
hf - converts raw internet addresses to hostnames.
ef - converts ethernet addresses to hostnames.
nf - converts network addresses to names.
pf - converts square bracketed port numbers to names.
Options common to all programs:
- -d
- Dump the hash table (usually for debugging purposes).
Options specific to
hf:
- -1
- Attempt to convert only the first address on a line.
- -a
- Use asynchronous dns lookups.
- -b
- Prints both the hostname and the ip address (the latter in parentheses).
This is a shortcut for -f "%h(%i)".
- -c
- Checks the names against ip addresses; that is, the hostname the address
resolves to must resolve back to the address or else the address is not
converted to a hostname.
- -f
- Specify a format string containing escapes to be used to create the
replacement text. The escapes are as follows:
%h - hostname (
%D,
%N,
%l or
even
%i)
%D - local domain truncated hostname
%N - domain truncated hostname
%l - long hostname (FQDN)
%i - ip address
%% -
%
Unrecognized escapes expand to the character without the
percent. It's acceptable to use specific escapes more than once. Specifying an
empty format resets it to the default ("%h").
- -i
- Force converted names to be all lowercase.
- -l
- By default, hf strips the domain part of hostnames in the local
domain. The -l flag suppresses this stripping.
- -N
- Strips the entire domain of all hostnames.
- -t
- Specify a timeout (in seconds) for name and address lookups. By default,
timeouts are left up to the resolver routines.
- -x
- Instead of replacing ip addresses with names, just output the raw ip
addresses, one per line. No other flags are allowed (or would even make
sense).
Options specific to
nf:
- -i
- Force converted names to be all lowercase.
- -b
- Prints both the hostname and the ip address (the latter in
parentheses).
- -p
- Pad network addresses to four octets.
gethostbyaddr(3), ether_aton(3), getnetbyaddr(3), getservbyport(3)
If a port number has different tcp and udp names,
pf will favor the tcp
name.