(PHP 3, PHP 4 )
Searches DNS for records of type
type corresponding to
host. Returns TRUE
if any records are found; returns
FALSE if no records were found or if an error
occurred.
type may be any one
of: A, MX, NS, SOA, PTR, CNAME, AAAA, or ANY. The default is
MX.
Host may either be the
IP address in dotted-quad notation or the host name.
注: AAAA type added with PHP 4.3.0
See also getmxrr(),
gethostbyaddr(),
gethostbyname(),
gethostbynamel(), and the named(8) manual page.