3.9.3 Keywords applicable for tar --extract

The following keywords control warnings that can be issued during archive extraction.

warning: existing-file

%s: skipping existing file

warning: timestamp

%s: implausibly old time stamp %s
%s: time stamp %s is %s s in the future

warning: contiguous-cast

Extracting contiguous files as regular files

Attempting extraction of symbolic links as hard links’, warning message ‘Attempting extraction of symbolic links as hard links

warning: unknown-cast

%s: Unknown file type '%c', extracted as normal file

warning: ignore-newer

Current %s is newer or same age

warning: unknown-keyword

Ignoring unknown extended header keyword '%s'

warning: decompress-program

Controls verbose description of failures occurring when trying to run alternative decompressor programs (see alternative decompression programs). This warning is disabled by default (unless --verbose is used). A common example of what you can get when using this warning is:

$ tar --warning=decompress-program -x -f archive.Z
tar (child): cannot run compress: No such file or directory
tar (child): trying gzip

This means that tar first tried to decompress archive.Z using compress, and, when that failed, switched to gzip.

warning: record-size

Record size = %lu blocks