2 # Make sure that `tail -n0 -f' and `tail -c0 -f' sleep
3 # rather than doing what amounted to a busy-wait.
5 # Copyright (C) 2003, 2006-2009 Free Software Foundation, Inc.
7 # This program is free software: you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation, either version 3 of the License, or
10 # (at your option) any later version.
12 # This program is distributed in the hope that it will be useful,
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program. If not, see <http://www.gnu.org/licenses/>.
20 # This bug was fixed for 5.0.91
21 # It skips the test if your system lacks a /proc/$pid/status
22 # file, or if its contents don't look right.
24 if test "$VERBOSE" = yes; then
31 require_proc_pid_status_
33 touch empty || framework_failure
34 echo anything > nonempty || framework_failure
38 for file in empty nonempty; do
40 tail --sleep=4 -${c_or_n} 0 -f $file &
43 set _ `sed -n '/^State:[ ]*\([^ ]\)/s//\1/p' /proc/$pid/status`
44 shift # Remove the leading `_'.
48 *) echo $0: process in unexpected state: $state 1>&2; fail=1 ;;