Deletion from ZIP files "fixes" headers

[stranger]

Hi,

Some ZIP files that were created by older ZIP programs might have a mismatch between the local file header and the central directory header.
When deleting a file through TC from such a ZIP file, TC "corrects" the headers of *all* files in the zip to have the local file headers align with the central directory headers.
I assume updating a ZIP file should have the very minimum impact on the file, and only the requested changes should be executed, so TC seems to be doing more than it should.

Thanks!

[Horst.Epp]

Why should TC zip write an illegal structure
only for the reason that there is already an error in the file.

[sqa_wizard]

To be more detailed:
You cannot just delete a file from a ZIP directly !
The ZIP has to be unpacked completely first and packed again without the file.
This way a correct header is written again.

[ghisler(Author)]

No, it doesn't have to be unpacked completely. TC creates a new temporary ZIP file and copies all not deleted files from the old to the new ZIP file. It copies the compressed data and doesn't unpack and then re-pack the data. But since it has to create a new ZIP, it creates it with correct headers.

[stranger]

No, it doesn't have to be unpacked completely. TC creates a new temporary ZIP file and copies all not deleted files from the old to the new ZIP file. It copies the compressed data and doesn't unpack and then re-pack the data. But since it has to create a new ZIP, it creates it with correct headers.

Is there a way to preserve the current header by simply copying the current values? I imagine that's a more "accurate" implementation, without any assumptions.