| \section{Built-in Module \sectcode{macdnr}} |
| \label{module-macdnr} |
| \bimodindex{macdnr} |
| |
| This module provides an interface to the Macintosh Domain Name |
| Resolver. It is usually used in conjunction with the \var{mactcp} |
| module, to map hostnames to IP-addresses. It may not be available in |
| all Mac Python versions. |
| |
| The \code{macdnr} module defines the following functions: |
| |
| \renewcommand{\indexsubitem}{(in module macdnr)} |
| |
| \begin{funcdesc}{Open}{\optional{filename}} |
| Open the domain name resolver extension. If \var{filename} is given it |
| should be the pathname of the extension, otherwise a default is |
| used. Normally, this call is not needed since the other calls will |
| open the extension automatically. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{Close}{} |
| Close the resolver extension. Again, not needed for normal use. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{StrToAddr}{hostname} |
| Look up the IP address for \var{hostname}. This call returns a dnr |
| result object of the ``address'' variation. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{AddrToName}{addr} |
| Do a reverse lookup on the 32-bit integer IP-address |
| \var{addr}. Returns a dnr result object of the ``address'' variation. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{AddrToStr}{addr} |
| Convert the 32-bit integer IP-address \var{addr} to a dotted-decimal |
| string. Returns the string. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{HInfo}{hostname} |
| Query the nameservers for a \code{HInfo} record for host |
| \var{hostname}. These records contain hardware and software |
| information about the machine in question (if they are available in |
| the first place). Returns a dnr result object of the ``hinfo'' |
| variety. |
| \end{funcdesc} |
| |
| \begin{funcdesc}{MXInfo}{domain} |
| Query the nameservers for a mail exchanger for \var{domain}. This is |
| the hostname of a host willing to accept SMTP mail for the given |
| domain. Returns a dnr result object of the ``mx'' variety. |
| \end{funcdesc} |
| |
| \subsection{dnr result object} |
| |
| Since the DNR calls all execute asynchronously you do not get the |
| results back immediately. Instead, you get a dnr result object. You |
| can check this object to see whether the query is complete, and access |
| its attributes to obtain the information when it is. |
| |
| Alternatively, you can also reference the result attributes directly, |
| this will result in an implicit wait for the query to complete. |
| |
| The \var{rtnCode} and \var{cname} attributes are always available, the |
| others depend on the type of query (address, hinfo or mx). |
| |
| \renewcommand{\indexsubitem}{(dnr result object method)} |
| |
| % Add args, as in {arg1\, arg2 \optional{\, arg3}} |
| \begin{funcdesc}{wait}{} |
| Wait for the query to complete. |
| \end{funcdesc} |
| |
| % Add args, as in {arg1\, arg2 \optional{\, arg3}} |
| \begin{funcdesc}{isdone}{} |
| Return 1 if the query is complete. |
| \end{funcdesc} |
| |
| \renewcommand{\indexsubitem}{(dnr result object attribute)} |
| |
| \begin{datadesc}{rtnCode} |
| The error code returned by the query. |
| \end{datadesc} |
| |
| \begin{datadesc}{cname} |
| The canonical name of the host that was queried. |
| \end{datadesc} |
| |
| \begin{datadesc}{ip0} |
| \dataline{ip1} |
| \dataline{ip2} |
| \dataline{ip3} |
| At most four integer IP addresses for this host. Unused entries are |
| zero. Valid only for address queries. |
| \end{datadesc} |
| |
| \begin{datadesc}{cpuType} |
| \dataline{osType} |
| Textual strings giving the machine type an OS name. Valid for hinfo |
| queries. |
| \end{datadesc} |
| |
| \begin{datadesc}{exchange} |
| The name of a mail-exchanger host. Valid for mx queries. |
| \end{datadesc} |
| |
| \begin{datadesc}{preference} |
| The preference of this mx record. Not too useful, since the Macintosh |
| will only return a single mx record. Mx queries only. |
| \end{datadesc} |
| |
| The simplest way to use the module to convert names to dotted-decimal |
| strings, without worrying about idle time, etc: |
| \bcode\begin{verbatim} |
| >>> def gethostname(name): |
| ... import macdnr |
| ... dnrr = macdnr.StrToAddr(name) |
| ... return macdnr.AddrToStr(dnrr.ip0) |
| \end{verbatim}\ecode |