William.Hatheway
Well-known member
I wanted to document a warning that may appear when extracting a .tar.gz geographic data package on Linux:
tar: Ignoring unknown extended header keyword
In my case, this appeared while extracting a geographic data archive such as:
geog_noahmp.tar.gz
The warning is caused by macOS extended file attributes being included in the tar archive when the package is created on a Mac. Specifically, macOS may attach the following quarantine attribute to downloaded files:
com.apple.quarantine
When the archive is later extracted on Linux using GNU tar, GNU tar does not recognize the Apple-specific LIBARCHIVE.xattr metadata, so it reports the warning and ignores that metadata.
This does not appear to indicate corruption of the geographic data, and it does not prevent the actual files from being extracted normally. The warning is related only to macOS metadata stored in the archive.
For anyone creating WRF/WPS or MPAS .tar.gz data packages on macOS, the metadata can be removed before packaging with:
xattr -dr com.apple.quarantine <directory>
It may also be useful to create the archive with Apple metadata disabled:
COPYFILE_DISABLE=1 tar -czf package.tar.gz <directory>/
For Linux users downloading and extracting an archive that already contains these attributes, the warnings can generally be safely ignored as long as the archive extracts successfully and the expected files are present.
I am posting this in case others encounter the same LIBARCHIVE.xattr.com.apple.quarantine messages while installing or updating WRF/WPS or MPAS geographic datasets.
tar: Ignoring unknown extended header keyword
Code:
'LIBARCHIVE.xattr.com.apple.quarantine'In my case, this appeared while extracting a geographic data archive such as:
geog_noahmp.tar.gz
The warning is caused by macOS extended file attributes being included in the tar archive when the package is created on a Mac. Specifically, macOS may attach the following quarantine attribute to downloaded files:
com.apple.quarantine
When the archive is later extracted on Linux using GNU tar, GNU tar does not recognize the Apple-specific LIBARCHIVE.xattr metadata, so it reports the warning and ignores that metadata.
This does not appear to indicate corruption of the geographic data, and it does not prevent the actual files from being extracted normally. The warning is related only to macOS metadata stored in the archive.
For anyone creating WRF/WPS or MPAS .tar.gz data packages on macOS, the metadata can be removed before packaging with:
xattr -dr com.apple.quarantine <directory>
It may also be useful to create the archive with Apple metadata disabled:
COPYFILE_DISABLE=1 tar -czf package.tar.gz <directory>/
For Linux users downloading and extracting an archive that already contains these attributes, the warnings can generally be safely ignored as long as the archive extracts successfully and the expected files are present.
I am posting this in case others encounter the same LIBARCHIVE.xattr.com.apple.quarantine messages while installing or updating WRF/WPS or MPAS geographic datasets.