diff --git a/IPython/utils/_process_common.py b/IPython/utils/_process_common.py
index 0843e89..f77cf59 100644
--- a/IPython/utils/_process_common.py
+++ b/IPython/utils/_process_common.py
@@ -15,6 +15,7 @@ of subprocess utilities, and it contains tools that are common to all of them.
 # Imports
 #-----------------------------------------------------------------------------
 import subprocess
+import shlex
 import sys
 
 from IPython.utils import py3compat
@@ -143,3 +144,27 @@ def getoutputerror(cmd):
         return '', ''
     out, err = out_err
     return py3compat.bytes_to_str(out), py3compat.bytes_to_str(err)
+
+
+def arg_split(s, posix=False):
+    """Split a command line's arguments in a shell-like manner.
+
+    This is a modified version of the standard library's shlex.split()
+    function, but with a default of posix=False for splitting, so that quotes
+    in inputs are respected."""
+
+    # Unfortunately, python's shlex module is buggy with unicode input:
+    # http://bugs.python.org/issue1170
+    # At least encoding the input when it's unicode seems to help, but there
+    # may be more problems lurking.  Apparently this is fixed in python3.
+    is_unicode = False
+    if (not py3compat.PY3) and isinstance(s, unicode):
+        is_unicode = True
+        s = s.encode('utf-8')
+    lex = shlex.shlex(s, posix=posix)
+    lex.whitespace_split = True
+    tokens = list(lex)
+    if is_unicode:
+        # Convert the tokens back to unicode.
+        tokens = [x.decode('utf-8') for x in tokens]
+    return tokens
diff --git a/IPython/utils/_process_posix.py b/IPython/utils/_process_posix.py
index 3147cb4..6227f35 100644
--- a/IPython/utils/_process_posix.py
+++ b/IPython/utils/_process_posix.py
@@ -18,13 +18,12 @@ from __future__ import print_function
 # Stdlib
 import subprocess as sp
 import sys
-import shlex
 
 from IPython.external import pexpect
 
 # Our own
 from .autoattr import auto_attr
-from ._process_common import getoutput
+from ._process_common import getoutput, arg_split
 from IPython.utils import text
 from IPython.utils import py3compat
 
@@ -194,28 +193,5 @@ class ProcessHandler(object):
 # (ls is a good example) that makes them hard.
 system = ProcessHandler().system
 
-def arg_split(s, posix=False):
-    """Split a command line's arguments in a shell-like manner.
-
-    This is a modified version of the standard library's shlex.split()
-    function, but with a default of posix=False for splitting, so that quotes
-    in inputs are respected."""
-
-    # Unfortunately, python's shlex module is buggy with unicode input:
-    # http://bugs.python.org/issue1170
-    # At least encoding the input when it's unicode seems to help, but there
-    # may be more problems lurking.  Apparently this is fixed in python3.
-    is_unicode = False
-    if (not py3compat.PY3) and isinstance(s, unicode):
-        is_unicode = True
-        s = s.encode('utf-8')
-    lex = shlex.shlex(s, posix=posix)
-    lex.whitespace_split = True
-    tokens = list(lex)
-    if is_unicode:
-        # Convert the tokens back to unicode.
-        tokens = [x.decode('utf-8') for x in tokens]
-    return tokens
-
 
 
diff --git a/IPython/utils/_process_win32.py b/IPython/utils/_process_win32.py
index 29e74d4..9de9edf 100644
--- a/IPython/utils/_process_win32.py
+++ b/IPython/utils/_process_win32.py
@@ -175,27 +175,4 @@ try:
         retval = LocalFree(result_pointer)
         return result
 except AttributeError:
-    import shlex
-    #alternative if CommandLineToArgvW is not available
-    def arg_split(s, posix=False):
-        """Split a command line's arguments in a shell-like manner.
-
-        This is a modified version of the standard library's shlex.split()
-        function, but with a default of posix=False for splitting, so that quotes
-        in inputs are respected."""
-
-        # Unfortunately, python's shlex module is buggy with unicode input:
-        # http://bugs.python.org/issue1170
-        # At least encoding the input when it's unicode seems to help, but there
-        # may be more problems lurking.  Apparently this is fixed in python3.
-        is_unicode = False
-        if (not py3compat.PY3) and isinstance(s, unicode):
-            is_unicode = True
-            s = s.encode('utf-8')
-        lex = shlex.shlex(s, posix=posix)
-        lex.whitespace_split = True
-        tokens = list(lex)
-        if is_unicode:
-            # Convert the tokens back to unicode.
-            tokens = [x.decode('utf-8') for x in tokens]
-        return tokens
+    from ._process_common import arg_split