coreutils/tests/tail-2/assert-2

#!/bin/sh
# This variant of `assert' would get a UMR reliably in 2.0.9.
# Due to a race condition in the test, the `assert' script would get
# the UMR on Solaris only some of the time, and not at all on Linux/GNU.

if test "$VERBOSE" = yes; then
  set -x
  tail --version
fi

tmp=tail-as2.$$
pwd=`pwd`
trap "cd $pwd; rm -rf $tmp" 0 1 2 3 15

test_failure=0
mkdir $tmp || test_failure=1
cd $tmp || test_failure=1

if test $test_failure = 1; then
  echo 'failure in testing framework'
  exit 1
fi

ok='ok ok ok'

touch a
tail --follow=name a foo > err 2>&1 &
tail_pid=$!
# Arrange for the tail process to die after 12 seconds.
(sleep 12; kill $tail_pid) &
echo $ok > f
echo sleeping for 7 seconds...
sleep 7
mv f foo

# echo waiting....
wait

case "`cat err`" in
  *$ok) fail=0;;
  *) fail=1;;
esac

test $fail = 1 && cat err

exit $fail