Ubuntu Manpage: transfer::data::destination

NAME

       transfer::data::destination - Data destination

SYNOPSIS

       package require Tcl  8.4

       package require snit  ?1.0?

       package require transfer::data::destination  ?0.2?

       transfer::data::destination objectName ?options...?

       objectName method ?arg arg ...?

       objectName destroy

       objectName put chunk

       objectName done

       objectName valid msgvar

       objectName receive channel done

_________________________________________________________________________________________________

DESCRIPTION

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

API

transfer::data::destination objectName ?options...?
This command creates a new data destination object with an associated Tcl command
whose name is objectName. This object command is explained in full detail in the
sections Object command and Object methods. The set of supported options is
explained in section Options.

The object command will be created under the current namespace if the objectName is
not fully qualified, and in the specified namespace otherwise. The fully qualified
name of the object command is returned as the result of the command.

OBJECT COMMAND
All objects created by the ::transfer::data::destination command have the following
general form:

objectName method ?arg arg ...?
The method method and its arg'uments determine the exact behavior of the command.
See section Object methods for the detailed specifications.

OBJECT METHODS
objectName 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.

objectName 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.

objectName 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.

objectName 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.

objectName receive channel done
This method initiates the reception of data from the specified channel. The
received data will be stored into the configured destination, 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.

OPTIONS
All data destinations support the options listed below. It should be noted that all are
semi-exclusive, each specifying a different type of destination 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.

-progress command
This option, if specified, defines a command to be invoked for each chunk of bytes
received, allowing the user to monitor the progress of the reception of the data.
The callback is always invoked with one additional argument, the number of bytes
received so far.

BUGS, IDEAS, FEEDBACK

       This  document,  and  the  package  it  describes, will undoubtedly contain bugs and other
       problems.   Please  report  such  in  the  category  transfer  of  the   Tcllib   Trackers
       [http://core.tcl.tk/tcllib/reportlist].  Please also report any ideas for enhancements you
       may have for either package and/or documentation.

KEYWORDS

       channel, copy, data destination, transfer

COPYRIGHT

       Copyright (c) 2006-2009 Andreas Kupries <andreas_kupries@users.sourceforge.net>