diff options
| -rw-r--r-- | NEWS | 5 | ||||
| -rw-r--r-- | src/tail.c | 7 | ||||
| -rw-r--r-- | tests/Makefile.am | 1 | ||||
| -rwxr-xr-x | tests/tail-2/flush-initial | 41 |
4 files changed, 53 insertions, 1 deletions
@@ -27,6 +27,11 @@ GNU coreutils NEWS -*- outline -*- because ls must stat every file in order to obtain a guaranteed-valid inode number. [bug introduced in coreutils-6.0] + tail -f (inotify-enabled) now flushes any initial output before blocking. + Before, this would print nothing and wait: stdbuf -o 4K tail -f /etc/passwd + Note that this bug affects tail -f only when its standard output is buffered, + which is relatively unusual. + ** New features cp --reflink accepts a new "auto" parameter which falls back to diff --git a/src/tail.c b/src/tail.c index fee3f1f2d..e3b9529f8 100644 --- a/src/tail.c +++ b/src/tail.c @@ -1399,7 +1399,6 @@ tail_forever_inotify (int wd, struct File_spec *f, size_t n_files, if (fflush (stdout) != 0) error (EXIT_FAILURE, errno, _("write error")); } - } #endif @@ -1990,6 +1989,12 @@ main (int argc, char **argv) error (0, errno, _("inotify cannot be used, reverting to polling")); else { + /* Flush any output from tail_file, now, since + tail_forever_inotify flushes only after writing, + not before reading. */ + if (fflush (stdout) != 0) + error (EXIT_FAILURE, errno, _("write error")); + tail_forever_inotify (wd, F, n_files, sleep_interval); /* The only way the above returns is upon failure. */ diff --git a/tests/Makefile.am b/tests/Makefile.am index d9ff95be4..d83d41b9b 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -427,6 +427,7 @@ TESTS = \ rmdir/t-slash \ tail-2/assert-2 \ tail-2/big-4gb \ + tail-2/flush-initial \ tail-2/proc-ksyms \ tail-2/start-middle \ touch/dangling-symlink \ diff --git a/tests/tail-2/flush-initial b/tests/tail-2/flush-initial new file mode 100755 index 000000000..2deff84f3 --- /dev/null +++ b/tests/tail-2/flush-initial @@ -0,0 +1,41 @@ +#!/bin/sh +# inotify-based tail -f didn't flush its initial output before blocking + +# Copyright (C) 2009 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 <http://www.gnu.org/licenses/>. + +if test "$VERBOSE" = yes; then + set -x + tail --version +fi + +. $srcdir/test-lib.sh + +fail=0 +echo line > in || fail=1 +stdbuf --output=1K tail -f in > out & +tail_pid=$! + +# Wait for the backgrounded `tail' to start. +while :; do + env kill -0 $tail_pid && break + sleep .1 +done + +test -s out || fail=1 + +kill $tail_pid + +Exit $fail |