Stu 2012-09-05 Mostly complete.
Stu 2012-08-27 Initial development version.
Documentation
NAME
treso - Resolver
SYNOPSIS
package require Tcl 8.6
package require treso 0.2
namespace import ::treso::*
treso::resolve ?-option ...? what ?-option ...?
treso::resolvers
treso::running
treso::cancel runId
DESCRIPTION
This extension uses the system's resolver to resolve
names to addresses or addresses to names. When resolving
addresses to names, the first address found is returned
unless one of the return options is given.
A single return option returns the option's value.
More than one return option or the -all return
option will return a dict of option/value pairs.
Lookups are performed in the inet domain by default.
RESOLVERS
The resolvers command returns a list of available resolvers
that may be passed as parameters to the -resolver option of
the resolve command. At minimum, four resolvers are available:
none Returns a result based on the input and options.
Doesn't attempt to resolve anything.
Possibly useful for testing.
Nonblocking.
simple Simple resolver.
Returns result directly.
Most likely blocking.
direct Direct resolver.
Calls callback immediately, before the resolve command returns.
Callback is called with one extra argument: the requested return data.
Returns an empty string.
Most likely blocking.
basync Blocking async resolver.
Creates an event that should happen immediately
and calls the callback from the event handler.
Callback is called with one extra argument: the requested return data.
Returns an identifier.
Needs event loop.
Most likely blocking.
The following resolvers may also be available:
thread Threaded resolver.
All potentially blocking operations happen in a thread.
Callback is called with one extra argument: the requested return data.
Returns an identifier.
Needs threads.
Needs event loop.
Nonblocking.
async Asynchronous resolver.
Callback is called with one extra argument: the requested return data.
Returns an identifier.
Needs event loop.
Nonblocking.
RESOLVERS COMMAND
The resolvers command returns a list of available resolvers.
RESOLVE COMMAND
The resolve command performs name resolution.
PARAMETERS
what Name or numeric address
RESOLVER OPTIONS
-domain domain Domain, inet or inet6
-resolver resolver Resolver to use
-answerto cmdprefix Callback
-to to Resolve to a name or addr, default name.
RETURN OPTIONS
-name Name
-aliases List of aliases
-addresses List of addresses
-domain Domain
-resolver Resolver
-to To
-all All of the above
RUNNING COMMAND
The running command returns a list of running queries.
CANCEL COMMAND
The cancel command cancels a running query.
Returns an empty string.
PARAMETERS
runId Run id to cancel
EXAMPLES
resolve localhost
resolve -aliases localhost -domain inet -addresses
resolve -domain -domain inet6 localhost
resolve -aliases -resolver basync localhost -answerto [list myproc someparm] -name
COPYRIGHT
Copyright (c) 2012 Stuart Cassoff