Ref: 17310013
Title: 3+ for Macintosh Wrongly Updates a File Modification Date
Date: 6/8/90

Copyright 3Com Corporation, 1991.  All rights reserved.

Note:  This article applies to 3+ for Macintosh version 1.6 and
previous versions.  The version of 3MACFS.EXE in the Patches and
Fixes library has not been subjected to exhaustive testing and may
not, in all circumstances, provide a complete solution.

A Macintosh data file which contains only a data fork, such as a
graphics or text file, can be copied from a local disk drive to a
shared network folder.   The creation date and modification date of
the copy match those of the original file still present on the
local disk.  Performing a GET INFO operation on the original file
as well as its duplicate stored in the 3+ shared directory will
confirm this.  If you repeat the GET INFO operation, it appears that
the file located in the 3+ directory has been modified at the time that
the operation was performed.

A file modification date should not change until the file is actually
modified.  However, performing a second GET INFO operation will reveal
that the first operation caused the modification date to be changed.
Subsequent GET INFO operations will not cause the modification date
to change.  For example:

1.  Place a data file, created by PC or Macintosh, into a 3+ shared
directory.

2.  Select the file located in the 3+ directory from the Finder on a
Macintosh netstation that is linked to the directory.

3.  Perform a GET INFO operation on the file on the file by pulling
down the file menu located on the Finder.

4.  Observe the last "file modified" date.

5.  Repeat the GET INFO operation for the same file.

6.  Notice that the "file modified" date has been updated.

When a file containing only a data fork is created in a shared network
folder, 3+ for Macintosh may not create a corresponding resource fork
file.  However, 3+ for Macintosh requires a resource fork to provide access
to Macintosh netstations.  When a Macintosh accesses the file, one is
created.  3+ for Macintosh then changes the "file modified" date.

Most Macintosh application programs are not affected by this action.
However, QuarkXPress by Quark does not accept a change to the
"file modified" date.  When QuarkXPress reads a data file with no
resource fork, one is created.  As a result, the "file modified" date
is updated although no file modification has been done.  Afterwards,
QuarkXPress can no longer interpret the data file.

A version of 3+ for Macintosh is available to correct this problem.  Obtain
the file 3MACFS.EXE from the Ask3Com Forum in the Patches and Fixes
library.  (Note:  This is not a released version of 3+ for Macintosh.
It has not been subjected to exhaustive testing and may not, in all
circumstances, provide a complete solution.)
