1 files changed, 7 insertions, 1 deletions
diff --git a/Lib/pydoc.py b/Lib/pydoc.py
index 594e6c7..0647d1e 100755
--- a/Lib/pydoc.py
+++ b/Lib/pydoc.py
@@ -1446,7 +1446,13 @@ def ttypager(text):
         getchar = lambda: sys.stdin.readline()[:-1][:1]
 
     try:
-        r = inc = os.environ.get('LINES', 25) - 1
+        try:
+            h = int(os.environ.get('LINES', 0))
+        except ValueError:
+            h = 0
+        if h <= 1:
+            h = 25
+        r = inc = h - 1
         sys.stdout.write(join(lines[:inc], '\n') + '\n')
         while lines[r:]:
             sys.stdout.write('-- more --')