doc: NEWS item for who systemd fix

2026-04-19T18:50:56Z

df: improve detection of duplicate entries

2026-04-15T11:56:16Z

Do not compare only with the latest entry for given device id but also all previously saved entries with the same id. * src/df.c (struct devlist): Add next_same_dev struct member. (filter_mount_list): Iterate over next_same_dev to find duplicates. * tests/df/skip-duplicates.sh: Add test cases. * NEWS: Mention the improvement. https://redhat.atlassian.net/browse/RHEL-5649

cat: use splice if operating on pipes or if copy_file_range fails

2026-04-07T04:57:07Z

On a AMD Ryzen 7 3700X system: $ timeout 10 taskset 1 ./src/cat-prev /dev/zero \ | taskset 2 pv -r > /dev/null [1.67GiB/s] $ timeout 10 taskset 1 ./src/cat /dev/zero \ | taskset 2 pv -r > /dev/null [9.03GiB/s] On a Power10 system: $ taskset 1 ./src/yes | timeout 10 taskset 2 ./src/cat-prev \ | taskset 3 pv -r > /dev/null [12.9GiB/s] $ taskset 1 ./src/yes | timeout 10 taskset 2 ./src/cat \ | taskset 3 pv -r > /dev/null [81.8GiB/s] * NEWS: Mention the improvement. * src/cat.c: Include isapipe.h, splice.h, and unistd--.h. (splice_cat): New function. (main): Use it. * src/local.mk (noinst_HEADERS): Add src/splice.h. * src/splice.h: New file, based on definitions from src/yes.c. * src/yes.c: Include splice.h. (pipe_splice_size): Use increase_pipe_size from src/splice.h. (SPLICE_PIPE_SIZE): Remove definition, moved to src/splice.h. * tests/cat/splice.sh: New file, based on some tests in tests/misc/yes.sh. * tests/local.mk (all_tests): Add the new test.

doc: document cut(1) multi-byte and interface consolidation

2026-04-06T14:52:58Z

This patch set updates cut(1) to be multi-byte aware. It also reduces interface divergence across implementations. multi-byte awareness was added to the existing -c, n, and -d options. Also considered for compatibility are the -w, -F, and -O options, as these are present on at least two other common implementations. = Interface / New functionality = macOS, i18n, uutils, Toybox, Busybox, GNU -c x x x x x x -n x x x -w x x x -F x x x -O x x x -c is needed anyway as specified by all, including POSIX. -n is needed also as specified by i18n/macOS/POSIX -w is somewhat less important, but seeing as it's on two other common platforms (and its functionality is provided on two more), providing it is worthwhile for compat. -F and -O are really just aliases to other options so trivial to add, and probably worthwhile for compatibility. Interface / functionality notes: There is a slight divergence between -n implementations. There was already a difference between FreeBSD and i18n, and we've aligned with the more sensible FreeBSD implementation. Note the i18n -n implementation is otherwise buggy in any case, so I doubt this will be a practical compatibility concern. Actually -n is specified by POSIX, and it matches FreeBSD. Specifically our -n will not output a character unless the byte range encompasses _the end_ of the multi-byte character. I.e. the -b is a limit that is not passed, and thus ensures we don't output overlapping characters for separate cut invocations that do not have overlapping byte ranges. -d from toybox is not implemented. That's edge case functionality IMHO and not well suited to cut(1). This functionality is supported by awk, and regex functionality is best restricted to awk I think. cut is a significant part of the i18n patch, so it will be good to avoid that downstream divergence. Unfortunately there were no tests with the cut i18n implementation. Note the i18n cut implementation used fread() as so was not reponsive to new data < BUFSIZ, whereas this implementation uses read() and thus is responsive to data as it becomes available. = Performance = General performance notes: We prefer byte searching (with -d) as that can be much faster than character by character processing, and it's supported on single byte and UTF-8 charsets. We also use byte searching with -w on uni-byte locales. This was seen to give up to 100x perf increase over the i18n patch. Where we do use per character processing, we avoid conversion to wide char when processing ASCII data (mcel provides this optimization). This was seen to give a 14x performance increase over the i18n patch. We prefer memchr() and strstr() as these are tuned for specific platforms on glibc, even if memchr2() or memmem() are algorithmically better. We maintain the important memory behavior of only buffering when necessary. Performance testing: There are _lots_ of combinations and optimziation opportunities. I performance tested this patch set with the following setup: $ yes | head -n10M > sl.in $ yes $(yes eeeaae | head -n10K | paste -s -d,) | head -n10K > ll.in $ yes $(yes eeeaae | head -n9 | paste -s -d,) | head -n1M > as.in $ yes $(yes éééááé | head -n9 | paste -s -d，) | head -n1M \ > mb.in $ for type in sl ll as mb; do cat $type.in >/dev/null; for imp in '' src/; do # '' maps to the system i18n ver on Fedora echo ============ "${imp:-i18n}" $type ==============; for d in -d, -dc -d， -dç -w -b -c; do fields='-f1 -f10 -f100' test "$d" = "-b" && { fields='-b1 -b10 -b100'; d=''; } test "$d" = "-c" && { fields='-c1 -c10 -c100'; d=''; } for f in $fields; do for loc in C C.UTF-8; do # SKip -b for UTF-8 as no different test "$loc" = C.UTF-8 && echo "$f" | grep -q -- -b \ && continue # Skip multi-byte delimiter for C and not allowed test "$loc" = C && test $(echo -n "$d" | wc -c) -ge 4 \ && continue LC_ALL=$loc ${imp}cut $f $d /dev/null 2>/dev/null && hyperfine -m2 -M4 \ "LC_ALL=$loc ${imp}cut $f $d $type.in >/dev/null" || printf 'Benchmark 1: %s\n unsupported\n\n' \ "LC_ALL=$loc ${imp}cut $f $d $type.in >/dev/null" done; done; done; done; done After a little post-processing of the results, we get: -- cut-i18n | command | sl | ll | as | mb | | --------------- | -------- | -------- | -------- | -------- | | C -f1 -d, | 66.3 ms | 1.605 s | 145.9 ms | 366.4 ms | | UTF8 -f1 -d, | 65.8 ms | 1.593 s | 145.8 ms | 370.0 ms | | C -f10 -d, | 301.4 ms | 1.590 s | 161.8 ms | 126.7 ms | | UTF8 -f10 -d, | 303.5 ms | 1.599 s | 161.8 ms | 124.6 ms | | C -f100 -d, | 300.6 ms | 1.596 s | 162.1 ms | 126.7 ms | | UTF8 -f100 -d, | 301.3 ms | 1.595 s | 162.0 ms | 124.9 ms | | C -f1 -dc | 66.6 ms | 1.845 s | 179.1 ms | 365.7 ms | | UTF8 -f1 -dc | 73.8 ms | 1.878 s | 179.1 ms | 363.1 ms | | C -f10 -dc | 300.7 ms | 349.8 ms | 76.0 ms | 125.3 ms | | UTF8 -f10 -dc | 300.4 ms | 347.2 ms | 75.7 ms | 124.8 ms | | C -f100 -dc | 300.1 ms | 348.1 ms | 76.5 ms | 125.5 ms | | UTF8 -f100 -dc | 300.8 ms | 348.7 ms | 76.4 ms | 125.8 ms | | UTF8 -f1 -d， | 563.5 ms | 21.775 s | 1.963 s | 1.665 s | | UTF8 -f10 -d， | 833.6 ms | 20.504 s | 2.022 s | 1.612 s | | UTF8 -f100 -d， | 825.2 ms | 20.448 s | 2.009 s | 1.616 s | | UTF8 -f1 -dç | 563.7 ms | 21.827 s | 1.964 s | 2.319 s | | UTF8 -f10 -dç | 825.3 ms | 21.713 s | 2.011 s | 2.248 s | | UTF8 -f100 -dç | 831.6 ms | 20.505 s | 2.019 s | 2.276 s | | C -f1 -w | - | - | - | - | | UTF8 -f1 -w | - | - | - | - | | C -f10 -w | - | - | - | - | | UTF8 -f10 -w | - | - | - | - | | C -f100 -w | - | - | - | - | | UTF8 -f100 -w | - | - | - | - | | C -b1 | 60.8 ms | 1.596 s | 154.8 ms | 313.7 ms | | C -b10 | 51.6 ms | 1.594 s | 154.3 ms | 310.8 ms | | C -b100 | 51.4 ms | 1.594 s | 153.0 ms | 312.2 ms | | C -c1 | 60.7 ms | 1.597 s | 153.8 ms | 313.0 ms | | UTF8 -c1 | 526.5 ms | 14.662 s | 1.362 s | 1.573 s | | C -c10 | 51.8 ms | 1.591 s | 153.3 ms | 311.4 ms | | UTF8 -c10 | 436.9 ms | 14.450 s | 1.336 s | 1.563 s | | C -c100 | 51.0 ms | 1.593 s | 152.7 ms | 313.2 ms | | UTF8 -c100 | 426.7 ms | 14.429 s | 1.344 s | 1.551 s | -- src/cut | command | sl | ll | as | mb | | --------------- | -------- | -------- | -------- | -------- | | C -f1 -d, | 4.6 ms | 108.2 ms | 45.4 ms | 24.2 ms | | UTF8 -f1 -d, | 4.8 ms | 108.4 ms | 45.4 ms | 24.5 ms | | C -f10 -d, | 4.5 ms | 109.3 ms | 123.7 ms | 24.3 ms | | UTF8 -f10 -d, | 4.9 ms | 114.1 ms | 124.1 ms | 24.5 ms | | C -f100 -d, | 4.7 ms | 119.2 ms | 124.1 ms | 24.5 ms | | UTF8 -f100 -d, | 4.8 ms | 120.0 ms | 125.1 ms | 24.5 ms | | C -f1 -dc | 4.4 ms | 120.5 ms | 11.9 ms | 24.1 ms | | UTF8 -f1 -dc | 4.9 ms | 120.5 ms | 12.1 ms | 24.6 ms | | C -f10 -dc | 4.7 ms | 125.3 ms | 11.8 ms | 24.1 ms | | UTF8 -f10 -dc | 4.8 ms | 126.7 ms | 12.0 ms | 24.4 ms | | C -f100 -dc | 4.6 ms | 127.0 ms | 11.9 ms | 24.3 ms | | UTF8 -f100 -dc | 4.7 ms | 126.4 ms | 12.0 ms | 24.4 ms | | UTF8 -f1 -d， | 6.0 ms | 169.4 ms | 15.6 ms | 67.4 ms | | UTF8 -f10 -d， | 6.1 ms | 173.9 ms | 15.6 ms | 237.2 ms | | UTF8 -f100 -d， | 6.1 ms | 174.0 ms | 15.6 ms | 237.8 ms | | UTF8 -f1 -dç | 6.3 ms | 170.8 ms | 15.7 ms | 32.2 ms | | UTF8 -f10 -dç | 6.0 ms | 172.9 ms | 15.9 ms | 32.1 ms | | UTF8 -f100 -dç | 6.7 ms | 173.1 ms | 15.5 ms | 32.3 ms | | C -f1 -w | 159.6 ms | 170.1 ms | 69.1 ms | 98.9 ms | | UTF8 -f1 -w | 128.1 ms | 2.525 s | 246.5 ms | 1.086 s | | C -f10 -w | 183.3 ms | 199.2 ms | 74.6 ms | 105.0 ms | | UTF8 -f10 -w | 130.3 ms | 2.659 s | 276.5 ms | 1.099 s | | C -f100 -w | 183.8 ms | 202.5 ms | 74.1 ms | 103.6 ms | | UTF8 -f100 -w | 130.1 ms | 2.663 s | 276.6 ms | 1.097 s | | C -b1 | 65.0 ms | 110.2 ms | 22.4 ms | 35.6 ms | | C -b10 | 48.7 ms | 109.6 ms | 24.2 ms | 36.7 ms | | C -b100 | 48.7 ms | 110.6 ms | 19.0 ms | 36.6 ms | | C -c1 | 65.8 ms | 109.5 ms | 22.4 ms | 35.6 ms | | UTF8 -c1 | 63.2 ms | 1.130 s | 116.9 ms | 610.2 ms | | C -c10 | 48.7 ms | 109.8 ms | 24.3 ms | 36.8 ms | | UTF8 -c10 | 39.7 ms | 1.133 s | 118.7 ms | 610.0 ms | | C -c100 | 48.3 ms | 110.7 ms | 18.9 ms | 36.7 ms | | UTF8 -c100 | 39.4 ms | 1.141 s | 115.0 ms | 598.8 ms | In summary, compared to the i18n patch we're now as fast in all cases, and much faster in most cases. We can see the -f byte searching performing well, being 120x faster in the no matching delimiter case, to at least 3x faster in the matching delimiter case. When we resort to per character processing we also compare well, being 14x faster in the ASCII processing case (due to mcel short-circuiting the wide char conversion). Note the processing mb.in results above also show a 2x win in per character processing cases, but the i18n patch would have also picked that win up as it's achieved separately to this patch set: https://lists.gnu.org/r/coreutils/2026-03/msg00117.html

cut,fold,expand,unexpand: ensure we process all available characters

2026-04-06T14:52:56Z

* gl/lib/mbbuf.h: Adjust mbbuf_fill() to process full characters in the slop at the end of a read(). Previously valid characters in the last MCEL_LEN_MAX bytes were ignored until the next read(). * src/cut.c (cut_fields_bytesearch): Adjust to the new naming. * NEWS: Mention the fold(1) responsiveness fix, which was improved with the change from fread() to read(), and completed with this patch.

build: update to latest gnulib

2026-04-05T12:11:21Z

Pick up mbrto{c32,wc} optimizations on UTF-8 on GLIBC. Note configure.ac defines the required GNULIB_WCHAR_SINGLE_LOCALE. This speeds up wc -m by 2.6x, when processing non ASCII chars, and will similarly speed up per character processing in the impending cut multi-byte implementation. * NEWS: Mention the wc -m speed improvement.

tac: promptly diagnose write errors

2026-03-21T19:10:59Z

This patch also fixes a bug where 'tac' would print a vague error on some inputs: $ seq 10000 | ./src/tac-prev > /dev/full tac-prev: write error $ seq 10000 | ./src/tac > /dev/full tac: write error: No space left on device In this case ferror (stdout) is true, but errno has been set back to zero by a successful fclose (stdout) call. * src/tac.c (output): Call write_error() if fwrite fails. * tests/misc/io-errors.sh: Check that 'tac' prints a detailed write error. * NEWS: Mention the improvement.

timeout: don't exit immediately if the parent is the init process

2026-03-14T03:37:10Z

* src/timeout.c (main): Save the process ID before creating a child process. Check if the result of getppid is different than the saved process ID instead of checking if it is 1. * tests/timeout/init-parent.sh: New file. * tests/local.mk (all_tests): Add the new test. * NEWS: Mention the bug fix. Also mention that this change allows 'timeout' to work when reparented by a subreaper process instead of init.

dd: always diagnose partial writes on write failure

2026-03-12T21:19:33Z

* src/dd.c (dd_copy): Increment the partial write count upon failure. * tests/dd/partial-write.sh: Add a new test. * tests/local.mk: Reference the new test. * NEWS: Mention the bug fix. Fixes https://bugs.gnu.org/80583

doc: clarify a recent NEWS item

2026-03-12T20:05:58Z

* NEWS: It was ambiguous as to whether we quoted a range of observered throughputs. Clarify this was the old and new throughput on a single test system.

coreutils/NEWS, branch master