into-self-4

来自「实战Linux编程的原代码,希望对学驱动的人能有所帮助」· 代码 · 共 38 行

#!/bin/sh
# confirm that `mv symlink symlink' doesn't remove symlink
# Based on an example from David Luyer.

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

. $srcdir/../envvar-check

pwd=`pwd`
tmp=mv-slink2.$$
trap 'status=$?; cd $pwd; rm -rf $tmp && exit $status' 0
trap '(exit $?); exit' 1 2 13 15

framework_failure=0
mkdir $tmp || framework_failure=1
cd $tmp || framework_failure=1
touch file || framework_failure=1
ln -s file s || framework_failure=1

if test $framework_failure = 1; then
  echo 'failure in testing framework' 1>&2
  (exit 1); exit
fi

fail=0

# This must fail.
mv s s 2> /dev/null && fail=1

# But the symlink, s, must not be removed.
# Before 4.0.36, `s' would have been removed.
test -f s || fail=1

(exit $fail); exit