#### Description:

This attribute specifies the name of a file to which the Channel should write data. If specified it is used in preference to any sink function specified when the Channel was created.

Assigning a new value to this attribute will cause any previously opened SinkFile to be closed. The first subsequent call to astWrite will attempt to open the new file (an error will be reported if the file cannot be opened), and write data to it. All subsequent call to astWrite will write data to the new file, until the SinkFile attribute is cleared or changed.

Clearing the attribute causes any open SinkFile to be closed. All subsequent data writes will use the sink function specified when the Channel was created, or will write to standard output if no sink function was specified.

If no value has been assigned to SinkFile, a null string will be returned if an attempt is made to get the attribute value.

Type:

  String.

#### Applicability

##### FitsChan

When the FitsChan is destroyed, any headers in the FitsChan will be written out to the sink file, if one is specified (if not, the sink function used when the FitsChan was created is used). The sink file is a text file (not a FITS file) containing one header per line.

#### Notes:

- A new SinkFile will over-write any existing file with the same name unless the existing file is write protected, in which case an error will be reported.

- Any open SinkFile is closed when the Channel is deleted.

- If the Channel is copied or dumped (using astCopy or astShow) the SinkFile attribute is left in a cleared state in the output Channel (i.e. the value of the SinkFile attribute is not copied).

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