2 .\" Copyright 1998 by the Massachusetts Institute of Technology.
4 .\" Permission to use, copy, modify, and distribute this
5 .\" software and its documentation for any purpose and without
6 .\" fee is hereby granted, provided that the above copyright
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11 .\" software without specific, written prior permission.
12 .\" M.I.T. makes no representations about the suitability of
13 .\" this software for any purpose. It is provided "as is"
14 .\" without express or implied warranty.
16 .TH ARES_GETHOSTBYNAME 3 "25 July 1998"
18 ares_gethostbyname \- Initiate a host query by name
23 .B typedef void (*ares_host_callback)(void *\fIarg\fP, int \fIstatus\fP,
24 .B int \fItimeouts\fP, struct hostent *\fIhostent\fP)
26 .B void ares_gethostbyname(ares_channel \fIchannel\fP, const char *\fIname\fP,
27 .B int \fIfamily\fP, ares_host_callback \fIcallback\fP, void *\fIarg\fP)
32 function initiates a host query by name on the name service channel
37 gives the hostname as a NUL-terminated C string, and
39 gives the desired type of address for the resulting host entry. When the
40 query is complete or has failed, the ares library will invoke \fIcallback\fP.
41 Completion or failure of the query may happen immediately, or may happen
42 during a later call to \fIares_process(3)\fP, \fIares_destroy(3)\fP or
53 indicates whether the query succeeded and, if not, how it failed. It
54 may have any of the following values:
57 The host lookup completed successfully.
60 The ares library does not know how to find addresses of type
66 is composed entirely of numbers and periods, but is not a valid
67 representation of an Internet address.
70 There was no data returned to extract a result from.
81 The query was cancelled.
84 The name service channel
86 is being destroyed; the query will not be completed.
90 reports how many times a query timed out during the execution of the
93 On successful completion of the query, the callback argument
97 containing the name of the host returned by the query. The callback
98 need not and should not attempt to free the memory pointed to by
100 the ares library will free it when the callback returns. If the query
101 did not complete successfully,
106 .BR ares_process (3),
107 .BR ares_gethostbyaddr (3)
109 Greg Hudson, MIT Information Systems
111 Copyright 1998 by the Massachusetts Institute of Technology.