coreutils-9.10

[Bruce Dubbs]

New minor version.

[Bruce Dubbs]

• Noteworthy changes in release 9.10 (2026-02-04) [stable]

• Bug fixes

cp, install, and mv no longer enter an infinite loop copying sparse files with SEEK_HOLE. E.g., this was seen on ext4 when copying sparse files with extents that are being actively updated, and copy offload is not being used. [bug introduced in coreutils-9.9]

'date' no longer fails with format directives that return an empty string. [bug introduced in coreutils-9.9]

'dd seek=N of=FILE' no longer continues copying, overwriting FILE if it exists, if ftruncate fails. [bug introduced in coreutils-9.1]

du and ls no longer modify strings returned by getenv. POSIX says this is not portable. [bug introduced in fileutils-4.1.6]

'fmt' now correctly diagnoses read errors. Previously fmt generated a generic error for any read error. [bug introduced in coreutils-9.0]

md5sum --text correctly translates CRLF line endings with the MSYS2 runtime. This also applies to the sha*sum and b2sum utilities. [This bug was present in "the beginning".]

'numfmt' no longer drops custom suffixes from numbers it cannot fully parse. [bug introduced with numfmt in coreutils-8.21]

'tail -f --pid' can no longer exit upon receiving a non terminating signal. On older Linux systems it may have failed with "Interrupted system call". [bug introduced in coreutils-7.5]

'timeout' will now propagate all terminating signals to the monitored command. Previously 'timeout' could have exited and left the monitored command running. [bug introduced with timeout in coreutils-7.0]

wc now documents its --debug option, currently used to indicate the line count acceleration being used. [bug introduced in coreutils-9.0]

When built with clang -fno-inline, memory allocation issues are again handled in a defined manner. Previously programs may have crashed etc. after a failure to allocate memory. [bug introduced in coreutils-9.0]

• New Features

configure accepts a new --enable-single-binary=hardlinks mode to build the selected programs as hard links to a multi-call binary called "coreutils". This augments the existing "symlinks" and "shebangs" modes already supported by the --enable-single-binary option.

'stat' and 'tail' now know about the "guest-memfd" file system type. stat -f -c%T now reports the file system type, and tail -f uses polling for this file system.

'tail' now accepts the --debug option, which is currently used to detail the --follow implementation being used.

'du' now supports the short option -A corresponding to the existing long option --apparent-size, for compatibility with FreeBSD.

• Changes in behavior

All commands now markup option names in --help and man pages, with bold attributes, and hyperlinks into the online manual on gnu.org. The links can be configured with the --enable-manual-url configure option, and the bold highlighting with --disable-bold-man-page-references. At runtime all markup can be disabled with the TERM=dumb env var value.

'fmt' -w,--width no longer includes '\n' in the width of a line. I.e., the specified width is interpreted to be an _inclusive_ maximum.

'ls --hyperlink' now uses more standard format hyperlinks. 'ESC\' (ST) is now used as a delimiter, instead of '\a' (BEL).

'ptx' -t is no longer a no-op, and now sets the default width to 100 columns.

'timeout' now honors ignored signals and will not propagate them. E.g., timeout(1) in a shell backgrounded job, will not terminate upon receiving SIGINT or SIGQUIT, as these are ignored by default in shell background jobs.

'timeout -v -s 0' now prints the signal number 0 instead of EXIT.

The multi-call binary now only processes --help or --version options if it is installed with a name ending with "coreutils". This allows for more consistent handling of these options with unsupported commands.

• Improvements

The multi-call binary built with configure --enable-single-binary is reduced in size by 3.2% through the more efficient reuse of the cksum utility by the md5sum and sha*sum utilities.

'cksum' now validates its options more consistently. E.g., cksum --text --tag now fails like cksum --tag --text already did.

'cksum', 'du', and 'wc' now exit promptly upon receiving a write error, which is significant when processing many input files.

csplit, ls, and sort, now handle a more complete set of terminating signals.

'du' now processes directories with 10,000 or more entries up to 9 times faster on the Lustre file system.

'paste' now supports multi-byte --delimiters characters.

'pinky' will now exit immediately upon receiving a write error, which is significant when reading large plan or project files.

'readlink' and 'realpath' will now exit promptly upon receiving a write error, which is significant when canonicalizing multiple file names longer than PATH_MAX.

'timeout' on Linux will always terminate the child in the case where the timeout process itself dies, like when it receives a KILL signal for example.

• Build-related

Programs now port to C23 platforms that strictly check types when qualifier-generic functions like strchr are used.

'chcon' and 'runcon' stub binaries will be built on systems without libselinux, when configured using --with-selinux.

'kill' and 'uptime' are no longer built by default. These programs can be built with the --enable-install-program=kill,uptime configure option.