absolute-symlink.sh: check for absolute symlinks on a FreeBSD system

The purpose of this script is to detect absolute symlinks on
a machine, e.g.:

    /etc/localtime -> /usr/share/zoneinfo/UTC

Some of these absolute symbolic links can be created intentionally,
but it is usually better to use relative symlinks.

You can run the script after `make installworld', or any other
make targets thats installs files.

You can also check your local ports with:

   env ABSOLUTE_SYMLINK_DIRS=/usr/local ./absolute-symlink.sh

tools/build/absolute-symlink.sh

@@ -0,0 +1,49 @@
+#!/bin/sh
+# Copyright (c) Oct 2024 Wolfram Schneider <wosch@FreeBSD.org>
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# absolute-symlink.sh - check for absolute symlinks on a FreeBSD system
+#
+# The purpose of this script is to detect absolute symlinks on
+# a machine, e.g.: 
+#
+#    /etc/localtime -> /usr/share/zoneinfo/UTC
+#
+# Some of these absolute symbolic links can be created intentionally,
+# but it is usually better to use relative symlinks.
+#
+# You can run the script after `make installworld', or any other
+# make targets thats installs files.
+#
+# You can also check your local ports with:
+#    
+#   env ABSOLUTE_SYMLINK_DIRS=/usr/local ./absolute-symlink.sh
+
+
+PATH="/bin:/usr/bin"; export PATH
+LANG="C"; export LANG
+
+# check other directories as well
+: ${ABSOLUTE_SYMLINK_DIRS=""}
+
+find -s -H \
+  /bin \
+  /boot \
+  /etc \
+  /lib \
+  /libexec \
+  /sbin \
+  /usr/bin \
+  /usr/include \
+  /usr/lib \
+  /usr/lib32 \
+  /usr/libdata \
+  /usr/libexec \
+  /usr/sbin \
+  /usr/src \
+  /usr/share \
+  $ABSOLUTE_SYMLINK_DIRS \
+  -type l \
+  -ls | grep -Ea -- ' -> /'
+
+#EOF