tuna: Fix show_threads --cgroups run without a term

When tuna show_threads --cgroups is run without a term,
provide a default column size of 80 to fix a traceback
that occurred when querying the terminal size.

Signed-off-by: Leah Leshchinsky <lleshchi@redhat.com>
- Edited the commit title
- Edited the description
Signed-off-by: John Kacur <jkacur@redhat.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/tuna-cmd.py b/tuna-cmd.py
index 630c8bc..4e809dd 100755
--- a/tuna-cmd.py
+++ b/tuna-cmd.py
@@ -31,6 +31,7 @@ import procfs
 from tuna import tuna, sysfs
 import logging
 import time
+import shutil
 
 def get_loglevel(level):
     if level.isdigit() and int(level) in range(0,5):
@@ -440,9 +441,10 @@ def ps_show(ps, affect_children, thread_list, cpu_list,
 
 
     # Width of terminal in columns
-    columns = None
+    columns = 80
     if cgroups:
-        _, columns = os.popen('stty size', 'r').read().split()
+        if os.isatty(sys.stdout.fileno()):
+            columns = shutil.get_terminal_size().columns
 
     for pid in ps_list:
         ps_show_thread(pid, affect_children, ps, has_ctxt_switch_info,