China DOS Union

Recently I found this:
Run DOSLFN with a Chinese font library
Then do a COPY operation on the following existing files:
C:\1\A.TXT already exists
C:\2\A.TXT already exists

COPY C:\1\A.TXT C:\2
It asks whether to overwrite? Press Y

Then go into C:\2 again,
A.TXT has changed into A~.TXT,

As long as I disable it with DOSLFN /U, this kind of operation works normally. I don't know whether it's a DOSLFN problem, a problem with the Chinese font library made by Wengier, or a problem with my runtime environment.

Runtime environment:
DOS71 + TW3.1

I just tested this issue in the Bochs virtual machine a moment ago.

In an MS-DOS 7.10 environment with DOSLFN (latest version) loaded (installed using the "MS-DOS 7.10 full installation edition", both C:\1\A.TXT and C:\2\A.TXT already existed, but this issue clearly could not be reproduced in the test, so it can be seen that it is not a DOSLFN problem.

As for the TW Chinese character support system, since TW cannot run in Bochs, it was not loaded. But since TW itself should not have any effect on this, I don't think it would be a TW problem.

So I think it may be a problem with your runtime environment or some other cause.

It is a doslfn problem, and this is related to the tbl file. If a.txt is renamed to uppercase A.TXT, then this problem does not occur. I have also run into this problem many times. Perhaps some hidden parameters of doslfn are taking effect. I mentioned this problem before, but there was no result.

DOS-era newbie: I tried both lowercase a.txt and uppercase A.TXT, but did not find any problem in either case. I now roughly know the reason: the DOSLFN version used by you and gmy is too old. The one I use is the latest version of DOSLFN, so I did not encounter this problem. Note: the latest version of DOSLFN is already automatically installed and automatically loaded in "MS-DOS 7.10 full installation edition".