QUERY(1)QUERY(1)NAMEquery - query nameservers through resolver library calls
SYNOPSISquery [-n nameserver] [-t type] [-c class] [-r retry] [-p retry period]
[-d] [-s] [-v] host
The query 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 argu‐
ments except for host and ns are treated without case-sensitivity.
OPTIONS-n The nameserver to be used in the query. Nameservers can
appear as either Internet addresses of the form w.x.y.z or
can appear as domain names. (default: as specified in
-t The type of resource record of interest. Types include:
CNAME canonical name
PTR domain name pointer
SOA start of authority
WKS well-known service
HINFO host information
MINFO mailbox information
MX mail exchange
RP responsible person
MG mail group member
DCE or AFS server
Note that any case may be used. (default: ANY)
-c The class of resource records of interest. Classes include:
Note that any case may be used. (default: IN)
-r The number of times to retry if the nameserver is not
responding. (default: 4)
-p Period to wait before timing out. (default: RES_TIMEOUT)
options field. (default: any answer)
-d Turn on debugging. This sets the RES_DEBUG bit of the
resolver's options field. (default: no debugging)
-s Use a stream rather than a packet. This uses a TCP stream
connection with the nameserver rather than a UDP datagram.
This sets the RES_USEVC bit of the resolver's options field.
-v Synonym for the 's' flag.
host The name of the host (or domain) of interest.
/etc/resolv.conf to get the default ns and search lists
<arpa/nameser.h> list of usable RR types and classes
<resolv.h> list of resolver flags
SEE ALSOnslookup(1), nstest(1), nsquery(1), named(8), resolver(5)DIAGNOSTICS
If the resolver fails to answer the query and debugging has not been
turned on, query will simply print a message like:
Query failed (rc = 1) : Unknown host
The value of the return code is supplied by h_errno.
Queries of a class other than IN can have interesting results since
ordinarily a nameserver only has a list of root nameservers for class
IN resource records.
Query uses a call to inet_addr() to determine if the argument for the
'-n' option is a valid Internet address. Unfortunately, inet_addr()
seems to cause a segmentation fault with some (bad) addresses (e.g.
4.3 Berkeley Distribution 10 March 1990 QUERY(1)