Make launcher find python binary

1 files changed, 17 insertions, 1 deletions

diff --git a/bin/dotbot b/bin/dotbot
index e9b432b..78a0725 100755
--- a/bin/dotbot
+++ b/bin/dotbot
@@ -1,4 +1,20 @@
-#!/usr/bin/env python
+#!/usr/bin/env sh
+
+# This is a valid shell script and also a valid Python script. When this file
+# is executed as a shell script, it finds a python binary and executes this
+# file as a Python script, passing along all of the command line arguments.
+# When this file is executed as a Python script, it loads and runs Dotbot. This
+# is useful because we don't know the name of the python binary.
+
+''':' # begin python string; this line is interpreted by the shell as `:`
+which python3 >/dev/null 2>&1 && exec python3 "$0" "$@"
+which python  >/dev/null 2>&1 && exec python  "$0" "$@"
+which python2 >/dev/null 2>&1 && exec python2 "$0" "$@"
+>&2 echo "error: cannot find python"
+return 1
+'''
+
+# python code
 
 import sys, os