diff --git a/pywal/sequences.py b/pywal/sequences.py
index b5bff82..7a67aec 100644
--- a/pywal/sequences.py
+++ b/pywal/sequences.py
@@ -83,7 +83,7 @@ def send(colors, cache_dir=CACHE_DIR, to_send=True,
 
     # Writing to "/dev/pts/[0-9] lets you send data to open terminals.
     if to_send:
-        ttys = []
+        ttys = None
         if only_active:
             ttys = util.fetch_active_ttys()
 
diff --git a/pywal/settings.py b/pywal/settings.py
index cb32c42..e040087 100644
--- a/pywal/settings.py
+++ b/pywal/settings.py
@@ -13,7 +13,7 @@ import os
 import platform
 
 
-__version__ = "3.3.1"
+__version__ = "3.3.2"
 __cache_version__ = "1.1.0"
 
 
diff --git a/pywal/util.py b/pywal/util.py
index aac8c57..787494b 100644
--- a/pywal/util.py
+++ b/pywal/util.py
@@ -134,7 +134,7 @@ def save_file(data, export_file):
         logging.warning("Couldn't write to %s.", export_file)
 
 
-def save_to_tty(data, tty_name, active_ttys=[]):
+def save_to_tty(data, tty_name, active_ttys=None):
     """Write data to a tty."""
     if active_ttys:
         if os.path.basename(tty_name) not in active_ttys:
@@ -144,6 +144,8 @@ def save_to_tty(data, tty_name, active_ttys=[]):
 
 
 def fetch_active_ttys():
+    """Fetches the active ttys as determined
+       by the `who` utility. On failure, we return None."""
     try:
         out, err = subprocess.Popen(
                 ["who"], stdout=subprocess.PIPE).communicate()