tests: check I/O error handling with /dev/full and closed pipes

* tests/misc/io-errors.sh: Verify that all commands diagnose write
errors, and handle a closed pipe appropriately.
* tests/local.mk: Reference the new test.

tests/local.mk

@@ -180,6 +180,7 @@ all_tests =					\
   tests/cp/link-heap.sh				\
   tests/cp/no-ctx.sh				\
   tests/tty/tty-eof.pl				\
+  tests/misc/io-errors.sh			\
   tests/misc/read-errors.sh			\
   tests/misc/write-errors.sh			\
   tests/tail/basic-seek.sh			\

tests/misc/io-errors.sh

@@ -0,0 +1,94 @@
+#!/bin/sh
+# Make sure all of these programs promptly diagnose write errors.
+
+# Copyright (C) 2025 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ env
+
+if ! test -w /dev/full || ! test -c /dev/full; then
+  skip_ '/dev/full is required'
+fi
+
+echo foo > foo || framework_failure_
+
+# Specific write paths to check in addition to --version.
+# Note writers that may output data indefinitely
+# are handled in write-errors.sh
+# First word in command line is checked against built programs
+{
+printf '%s' "\
+cat foo
+comm foo foo
+cut -c1- foo
+cut -f1- foo
+date +%s
+dd status=none if=foo
+expand foo
+factor 1
+fmt foo
+fold foo
+fold -b foo
+fold -c foo
+head -n1 foo
+join foo foo
+nl foo
+numfmt --invalid=ignore < foo
+od -v foo
+paste foo
+pr foo
+seq 1
+tail -n1 foo
+tee < foo
+tr . . < foo
+unexpand foo
+uniq foo
+";
+printf '%s --version\n' $built_programs;
+} |
+sort -k 1b,1 > all_writers || framework_failure_
+
+printf '%s\n' $built_programs |
+sort -k 1b,1 > built_programs || framework_failure_
+
+join all_writers built_programs > built_writers || framework_failure_
+
+while read writer; do
+
+  # Skip edge cases
+  printf '%s' "$writer" | grep -E '^(test|false|true|install)' &&
+    { echo "Skipping $writer" >&2; continue; }
+
+  # Check /dev/full diagnosed.
+  # Note we usually give a specific diagnostic (ENOSPC),
+  # but that's not guarantted in the generic close_stream() handling.
+  # For e.g. with _IOLBF etc, stdio will discard pending data at each line,
+  # thus only giving a generic error upon ferror() in close_stream().
+  rm -f full.err || framework_failure_
+  timeout 10 env --default-signal=PIPE $SHELL -c \
+    "(env $writer 2>full.err >/dev/full)"
+  { test $? = 124 || ! grep -E 'write error|space' full.err >/dev/null; } &&
+   { fail=1; cat full.err; echo "$writer: failed to exit" >&2; }
+
+  # Check closed pipe handling
+  rm -f pipe.err || framework_failure_
+  timeout 10 env --default-signal=PIPE $SHELL -c \
+    "(env $writer 2>pipe.err | :)"
+  { test $? = 0 && compare /dev/null pipe.err; } ||
+   { fail=1; cat pipe.err; echo "$writer: failed writing to closed pipe" >&2; }
+done < built_writers
+
+Exit $fail