transfer::data::destination(n)				     Data transfer facilities				    transfer::data::destination(n)

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NAME

       transfer::data::destination - Data destination

SYNOPSIS

       package require Tcl  8.4

       package require snit  ?1.0?

       package require transfer::data::destination  ?0.1?

       transfer::data::destination object ?options...?

       object destroy

       object put chunk

       object done

       object valid msgvar

       object receive channel done

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DESCRIPTION

       This  package provides objects mainly describing the destination of a data transfer. They are also able to initiate the reception of infor-
       mation from a channel into the described destination.

API

       transfer::data::destination object ?options...?
	      This command creates and configures a new destination object. The fully qualified name of the object  command  is  returned  as  the
	      result of the command.

	      The  recognized options are listed below. It should be noted that all are semi-exclusive, each specifying a different type of desti-
	      nation and associated information. If these options are specified more than once then the last option specified is used to  actually
	      configure the object.

	      -channel handle
		     This option specifies that the destination of the data is a channel, and its associated argument is the handle of the channel
		     to write the received data to.

	      -file path
		     This option specifies that the destination of the data is a file, and its associated argument is the  path  of  the  file	to
		     write the received data to.

	      -variable varname
		     This  option  specifies  that the destination of the data is a variable, and its associated argument contains the name of the
		     variable to write the received data to. The variable is assumed to be global or namespaced, anchored at the global namespace.

       object destroy
	      This method destroys the object. Doing so while the object is busy with the reception of	information  from  a  channel  will  cause
	      errors later on, when the reception completes and tries to access the now missing data structures of the destroyed object.

       object put chunk
	      The  main  receptor  method. Saves the received chunk of data into the configured destination. It has to be called for each piece of
	      data received.

       object done
	      The secondary receptor method. Finalizes the receiver. It has to be called when the receiving channel signals EOF. Afterward neither
	      itself nor method put can be called anymore.

       object valid msgvar
	      This  method  checks  the  configuration of the object for validity. It returns a boolean flag as result, whose value is True if the
	      object is valid, and False otherwise. In the latter case the variable whose name is stored in msgvar is  set  to	an  error  message
	      describing the problem found with the configuration. Otherwise this variable is not touched.

       object receive channel done
	      This  method initiates the reception of data from the specified channel. The received data will be stored into the configured desti-
	      nation, via calls to the methods put and done.  When the reception completes the command prefix done is invoked, with the number	of
	      received characters appended to it as the sole additional argument.

KEYWORDS

       channel, copy, data destination, transfer

COPYRIGHT

       Copyright (c) 2006 Andreas Kupries <andreas_kupries@users.sourceforge.net>

transfer								0.1					    transfer::data::destination(n)