[NetBSD] cmdline() raise ZombieProcess when unable to decode chars (#1536)

* bug #1536 / NetBSD / cmdline: treat EINVAL as 'return []'

This happens with unicode test, meaning the C routine it's
unable to decode the unicode chars.
Also, fix a bug introduced in 1530 (C impl of cwd()) which does not take
ENOENT into account.

1 files changed, 3 insertions, 4 deletions

diff --git a/psutil/_psbsd.py b/psutil/_psbsd.py
index 9964f5ff..978ad6c8 100644
--- a/psutil/_psbsd.py
+++ b/psutil/_psbsd.py
@@ -648,10 +648,9 @@ class Process(object):
                 return cext.proc_cmdline(self.pid)
             except OSError as err:
                 if err.errno == errno.EINVAL:
-                    if not pid_exists(self.pid):
-                        raise NoSuchProcess(self.pid, self._name)
-                    else:
-                        raise ZombieProcess(self.pid, self._name, self._ppid)
+                    # XXX: this happens with unicode tests. It means the C
+                    # routine is unable to decode invalid unicode chars.
+                    return []
                 else:
                     raise
         else: