#!/bin/sh
# Ensure that "tail -f fifo" tails indefinitely.

# Copyright (C) 2009-2012 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/>.

. "${srcdir=.}/init.sh"; path_prepend_ ../src
print_ver_ tail

mkfifo_or_skip_ fifo

echo 1 > fifo &
echo 1 > exp || framework_failure_

timeout 10 tail -f fifo > out & pid=$!

check_tail_output()
{
  local n_sec="$1"
  test -s out || { sleep $n_sec; return 1; }
}

# Wait 6.3s for tail to write something.
retry_delay_ check_tail_output .1 7 || fail=1

compare exp out || fail=1

# Kill the still-running tail, or fail if it's gone.
kill $pid || fail=1

Exit $fail