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DORs are manipulated using the OS_Dor call, which is supplied with various reason codes, one for each DOR operation. The possible operations are:
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Each reason code operation action is described in detail with the OS_Dor call in the "System Calls Reference" section.
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The following example reads the last updated date of a file, which can only be done by reading the DOR of the file. To get a DOR handle for a file, the user must use the GN_Opf call with A = OP_DOR ($06). This differs from the other options of GN_Opf in that:
1) It does not open the file. 2) It returns a DOR handle rather than a file handle
Note that the file should be closed before the call is made, and that it is necessary to free the DOR handle after you have finished, by using OS_Dor with reason code DR_FRE.
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