NAME

hf, ef, nf, pf - address to name filters

SYNOPSIS

hf [-1abcdilN] [-f format] [-t secs] [file ...] hf -x [file ...] ef [-d] [file ...] nf [-di] [file ...] pf [-d] [file ...]

DESCRIPTION

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:

OPTIONS

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:

-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.

SEE ALSO

gethostbyaddr(3), ether_aton(3), getnetbyaddr(3), getservbyport(3)

BUGS

If a port number has different tcp and udp names, pf will favor the tcp name.