diff --git a/toolbox/generate-input.h-labels.py b/toolbox/generate-input.h-labels.py
index 4d79043..ebb9588 100755
--- a/toolbox/generate-input.h-labels.py
+++ b/toolbox/generate-input.h-labels.py
@@ -36,7 +36,7 @@
 
 r = re.compile(r'#define\s+(\S+)\s+((?:0x)?\d+)')
 
-with open(os.environ['ANDROID_BUILD_TOP'] + '/bionic/libc/kernel/uapi/linux/input.h', 'r') as f:
+with open('bionic/libc/kernel/uapi/linux/input.h', 'r') as f:
   for line in f:
     m = r.match(line)
     if m: