GNU Coreutils is the backbone of many enterprise Linux environments. It provides the basic file, shell, and text utilities that every GNU-based system depends on. The latest release, version 9.9, refines these tools with fixes and performance improvements.
Several long-standing issues have been resolved. The basenc --base58 command now works properly with large inputs, correcting a bug introduced in version 9.8. The cksum utility improves support for base64 encoded input and tagged formats used with SHA2 algorithms. The cp command restores performance when handling transparently compressed files, fixing a slowdown seen on systems using OpenZFS.
Other fixes address system-specific behavior. On macOS, the env command will no longer set an unnecessary environment variable when built without localization support. On GNU/Hurd, nice now limits adjusted values to supported ranges. The numfmt tool has been hardened against out-of-bounds reads and invalid output when dealing with multi-byte blanks. The rm -d DIR command now behaves as expected on Ceph snapshot directories, and tail once again outputs the correct number of lines for large input values.
Some commands have adjusted behavior to align with these fixes. The cp command may again miss chances to create sparse files on certain file systems, a side effect of restoring copy performance. The sort command continues running even if its chosen compression program cannot be executed, avoiding silent failures.
Coreutils 9.9 adds a small but useful feature to numfmt, which now supports the --unit-separator option to specify a character between numbers and units.
The release also improves the reliability of several utilities. Programs like fmt, date, nl, and pr now exit immediately after encountering write errors, which helps when processing large or continuous data. Tools including install, sort, and split use posix_spawn() for better process handling. The wc -l command also gains a speed boost of about ten percent on hardware with AVX512 support.
Coreutils is availble for free download here.