Release Notes: The option "--recursive" has been added to zgrep. All the utilities have been rewritten in C++, making them safer and more efficient. Zcat and zcmp implement the functionality of cat and cmp respectively. Cat and cmp are not needed at runtime. All mentions to zegrep and zfgrep have been removed from the documentation because egrep and fgrep are deprecated.
Release Notes: The utility ztest, able to recursively test all the compressed files in a directory tree, has been added. The option "--recursive" has been added to zcat.
Release Notes: This release automatically recognizes the format of data read from stdin.
Release Notes: Two new utilities have been added: zegrep and zfgrep. Zutils now recognizes file formats independently of filename extensions.
Release Notes: A default compressor is no longer needed. All supported filename extensions are now tried.
Release Notes: Support for the xz compressor has been added.