Edit ZIP Comments and File Names Safely with zipnote

You will use zipnote to inspect the comments in a ZIP archive, edit that note format, and apply the change back to the archive. The same workflow can rename entries inside the archive. The original archive stays available until you have checked the result.

The examples use Info-ZIP ZipNote 3.0 from the Ubuntu zip package, version 3.0-13ubuntu0.2, installed on this machine. Allow about ten minutes. You need a shell, a writable working directory, and a ZIP file you are allowed to change. None of the normal commands needs sudo.

1. Confirm the installed command

Check which executable will run and record its version. These are read-only checks:

$ command -v zipnote
/usr/bin/zipnote
$ dpkg-query -W -f='${Package} ${Version}\n' zip
zip 3.0-13ubuntu0.2
$ zipnote -v
This is ZipNote 3.0 (July 5th 2008).

The exact copyright and build lines can vary, but the important result is the installed ZipNote version. The local manual describes this release as supporting ordinary ZIP archives, but not large archives over 2 GB or split archives.

2. Export the archive note to a working file

In this guide, replace /path/to/archive.zip with your archive. Redirect the output to a new file so you can inspect it before changing anything:

$ zipnote /path/to/archive.zip > /tmp/archive.zipnote
$ sed -n '1,80p' /tmp/archive.zipnote
@ document.txt
@ (comment above this line)
@ (zip file comment below this line)

With no options, zipnote writes the archive's comments to standard output. The output also lists each entry, even when the entry has no comment. The temporary file is plain text, but its markers are a strict input format. Do not turn it into a general text template or remove lines merely to make it look tidier.

If the command cannot open the archive, stop and check the path and permissions:

$ test -r /path/to/archive.zip && echo readable
readable
$ file /path/to/archive.zip
/path/to/archive.zip: Zip archive data

3. Back up before applying an edit

Make a copy in the same filesystem or another trusted location. Choose a backup name that will not be confused with the working archive:

$ cp --preserve=all /path/to/archive.zip /path/to/archive.zip.before-zipnote
$ ls -l /path/to/archive.zip /path/to/archive.zip.before-zipnote

$ cp --preserve=all /path/to/archive.zip.before-zipnote /path/to/archive.zip

4. Add or replace an archive comment

Open /tmp/archive.zipnote in a text editor and find the final marker:

@ (zip file comment below this line)

Put the archive comment on the following line. For example:

@ (zip file comment below this line)
Nightly export. Retain until 2030-12-31.

Preserve the other marker lines and entry names exactly. Do not include shell prompts, Markdown fences or the temporary file's path in the note file. The comment is archive metadata, so avoid placing credentials, access tokens or private material in it. Anyone who can read the ZIP may be able to read the comment.

Apply the edited note file by feeding it to zipnote -w:

$ zipnote -w /path/to/archive.zip < /tmp/archive.zipnote
$ printf 'zipnote exit status: %s\n' "$?"
zipnote exit status: 0

A zero status means the update command completed. It is not a substitute for reading the archive again.

5. Rename an entry without extracting it

Export the current format again if you are starting a separate rename, so you do not accidentally apply an old edit:

$ zipnote /path/to/archive.zip > /tmp/archive-rename.zipnote

For the entry named document.txt, change the adjacent section from this:

@ document.txt
@ (comment above this line)

to this:

@ document.txt
@=reports/document-final.txt

The @= line supplies the new entry name. Keep the original @ name line as the selector. Then apply it:

$ zipnote -w /path/to/archive.zip < /tmp/archive-rename.zipnote
$ zipinfo -1 /path/to/archive.zip | grep -Fx 'reports/document-final.txt'
reports/document-final.txt

The rename changes the name stored in the archive. It does not create a directory on disk and does not move an extracted file. If zipinfo is unavailable, export with zipnote again and search the output:

$ zipnote /path/to/archive.zip | grep -F 'reports/document-final.txt'
@ reports/document-final.txt

6. Validate the final archive

Re-export the note format and check the expected comment or name. A second tool can check the archive structure if it is installed:

$ zipnote /path/to/archive.zip | sed -n '1,40p'
$ unzip -t /path/to/archive.zip
No errors detected in compressed data of /path/to/archive.zip.

The output from unzip -t depends on the archive and the installed unzip version. Treat a non-zero status as a failed verification. Keep the backup until the entries, comments and content test all look right.

Common traps are predictable. Forgetting -w only prints a report and changes nothing. Using -w without redirecting the edited text makes the command wait for input from the terminal.

A malformed marker or an unmatched entry name can be rejected because ZipNote is deliberately picky about its temporary format. If an update fails, do not keep editing the same file blindly: restore the backup if the archive no longer passes its test, export a fresh note file, and make one small change.