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DCL: /SINCE and /BEFORE problems with opened files

The Question is:

A problem using /BEFORE/SINCE filters:

I have a program which continuously writes data to a text file.
Each 8 hours, the file is closed, and a new one is opened.  The
files have the same base name, but the date is coded in the
file name extension.  I want to copy the files to another VAX node
as they are closed, using a batch job.  Using the following
command:

$PRINT/SINCE=-8/BEFORE=-1 FILE_NAME NODE_2::*

The closed file is properly copied, but the command also tries
to copy the file just opened.  The command bombs out, because
my program has the open file locked.  I though that the
/BEFORE=-1 should filer out files created within the last hour.
The following command:

$DIR/SINCE=-9/BEFORE=-1 FILE_NAME

gives the expected result, reporting only the file created 8 hours
ago, an not the file created a few minutes ago.

What am I doing wrong?

The Answer is:

    Nothing. Just an unfortunate implementation detail.
    Most VMS utilities use a common set of routine to deal
    with file selection qualifiers such as /before and /exclu
    That package use RMS to get dates filled in through an OPEN.
    As you, and others, found out, that open can fail if the
    file is currently opened dis-allowing others.
    Directory, being more intimate with file headers and such,
    will uses a direct ACP QIO to get file attibutes with an
    option to ignore the file access lock.

    Suggestions:
    	- Teach the procedure to ignore the error:
    		$ON ERROR
    		:
    		$IF $STATUS .EQ...
    	- Use directory to build a list of file to copy:
    		$DIR/SINCE=-8/BEFORE=-1/NOHEAD/NOTRAIL ....
    	- Have the application change filenames after the close.