.\" $Id: dnsquery.1,v 8.2 1997/03/14 02:29:41 vixie Exp $
.\"
.\"Copyright (c) 1995, 1996 by Internet Software Consortium
.\"
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.\"purpose with or without fee is hereby granted, provided that the above
.\"copyright notice and this permission notice appear in all copies.
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.\"THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
.\"ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
.\"OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
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.\"DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
.\"PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
.\"ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
.\"SOFTWARE.
.\"
.Dd March 10, 1990
.Dt DNSQUERY @CMD_EXT_U@
.Os BSD 4
.Sh NAME
.Nm dnsquery 
.Nd query domain name servers using resolver
.Sh SYNOPSIS
.Nm dnsquery
.Op Fl n Ar nameserver
.Op Fl t Ar type
.Op Fl c Ar class
.Op Fl r Ar retry
.Op Fl p Ar period
.Op Fl d
.Op Fl s
.Op Fl v
.Ar host
.Sh DESCRIPTION
The
.Ic dnsquery
program is a general interface to nameservers via
BIND resolver library calls.  The program supports
queries to the nameserver with an opcode of QUERY.
This program is intended to be a replacement or
supplement to programs like nstest, nsquery and
nslookup.  All arguments except for
.Ar host
and
.Ar nameserver
are treated without case-sensitivity.
.Sh OPTIONS
.Bl -tag -width Fl
.It Fl n Ar nameserver
The nameserver to be used in the query.  Nameservers can appear as either 
Internet addresses of the form 
.Ar w.x.y.z 
or can appear as domain names.
(Default: as specified in 
.Pa /etc/resolv.conf . ) 
.It Fl t Ar type
The type of resource record of interest.  Types include:
.Bl -tag -width "AFSDB  " -compact -offset indent
.It Ar A
address
.It Ar NS
nameserver
.It Ar CNAME
canonical name
.It Ar PTR	
domain name pointer
.It Ar SOA	
start of authority
.It Ar WKS	
well-known service
.It Ar HINFO
host information
.It Ar MINFO
mailbox information
.It Ar MX	
mail exchange
.It Ar RP	
responsible person
.It Ar MG	
mail group member
.It Ar AFSDB	
DCE or AFS server
.It Ar ANY	
wildcard
.El
.Pp
Note that any case may be used.  (Default:  
.Ar ANY . )
.It Fl c Ar class
The class of resource records of interest.
Classes include:
.Bl -tag -width "CHAOS  " -compact -offset indent
.It Ar IN	
Internet
.It Ar HS	
Hesiod
.It Ar CHAOS
Chaos
.It Ar ANY	
wildcard
.El
.Pp
Note that any case may be used.  (Default:  
.Ar IN . )
.It Fl r Ar retry
The number of times to retry if the nameserver is
not responding.  (Default:  4.)
.It Fl p Ar period
Period to wait before timing out.  (Default:  
.Dv RES_TIMEOUT . )
.It Fl d
Turn on debugging.  This sets the 
.Dv RES_DEBUG 
bit of the resolver's
.Ft options
field.  (Default:  no debugging.)
.It Fl s
Use a
.Em stream
rather than a packet.  This uses a TCP stream connection with
the nameserver rather than a UDP datagram.  This sets the
.Dv RES_USEVC 
bit of the resolver's
.Ft options
field.  (Default:  UDP datagram.)
.It Fl v
Synonym for the 
.Dq Fl s 
flag.
.It Ar host
The name of the host (or domain) of interest.
.El
.Sh FILES
.Bl -tag -width "<arpa/nameser.h>  " -compact
.It Pa /etc/resolv.conf 
to get the default ns and search lists
.It Pa <arpa/nameser.h> 	
list of usable RR types and classes
.It Pa <resolv.h>		
list of resolver flags
.El
.Sh DIAGNOSTICS
If the resolver fails to answer the query and debugging has not been
turned on,
.Ic dnsquery
will simply print a message like:
.Dl Query failed (rc = 1) : Unknown host
.Pp
The value of the return code is supplied by 
.Ft h_errno .
.Sh SEE ALSO
.Xr nslookup @SYS_OPS_EXT@ , 
.Xr nstest @CMD_EXT@ , 
.Xr nsquery @CMD_EXT@ , 
.Xr named @SYS_OPS_EXT@ , 
.Xr resolver @FORMAT_EXT@ .
.Sh AUTHOR
Bryan Beecher
.Sh BUGS
Queries of a class other than 
.Ar IN 
can have interesting results
since ordinarily a nameserver only has a list of root nameservers
for class 
.Ar IN 
resource records.
.Pp
.Ic Dnsquery 
uses a call to 
.Fn inet_addr 
to determine if the argument
for the 
.Dq Fl n
option is a valid Internet address.  Unfortunately,
.Fn inet_addr 
seems to cause a segmentation fault with some (bad)
IP addresses (e.g., 1.2.3.4.5).