1 .\" Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
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32 .Nd "convert an IP number to the real host name"
40 .Fn realhostname "char *host" "size_t hsize" "const struct in_addr *ip"
46 to the corresponding host name.
47 This is done by resolving
49 to a host name and then ensuring that the host name resolves
54 must point to a buffer of at least
56 bytes, and will always be written to by this function.
58 If the name resolution doesn't work both ways or if the host name is longer
67 If the string written to
73 will not be NUL terminated.
77 function will return one of the following constants which are defined in
80 .Bl -tag -width XXX -offset XXX
82 A valid host name was found.
83 .It Li HOSTNAME_INCORRECTNAME
84 A host name was found, but it did not resolve back to the passed
87 now contains the numeric value of
89 .It Li HOSTNAME_INVALIDADDR
91 could not be resolved.
93 now contains the numeric value of
95 .It Li HOSTNAME_INVALIDNAME
96 A host name was found, but it could not be resolved back to any ip number.
98 now contains the numeric value of
102 .Xr gethostbyaddr 3 ,
103 .Xr gethostbyname 3 ,
105 .Xr realhostname_sa 3