From b2a608b0cff80be0e2b2227de2802493e68dfc73 Mon Sep 17 00:00:00 2001
From: gh2o <git@thegavinli.com>
Date: Sun, 13 Jul 2014 20:57:56 -0700
Subject: [PATCH] add checks

---
 install.sh | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/install.sh b/install.sh
index ceb8020..6a9cfe3 100755
--- a/install.sh
+++ b/install.sh
@@ -4,6 +4,17 @@
 archlinux_mirror="https://mirrors.kernel.org/archlinux/"
 preserve_home_directories=true
 
+stdin_symlink="$(readlink /dev/fd/0)"
+if [ "${stdin_symlink#pipe:}" != "${stdin_symlink}" ]; then
+	echo "This script must be run from a file. Exiting." >&2
+	exit 1
+fi
+
+if [ -n "${POSIXLY_CORRECT}" ] || [ -z "${BASH_VERSION}" ]; then
+	unset POSIXLY_CORRECT
+	exec bash "$0" "$@"
+fi
+
 set -eu
 set -o pipefail
 shopt -s nullglob
@@ -13,7 +24,6 @@ export LC_ALL=C
 export LANG=C
 unset LANGUAGE
 
-### VARIABLES
 declare -A dependencies
 dependencies[pacman]=x