Merge branch 'master' of github.com:giampaolo/psutil

7 files changed, 252 insertions, 310 deletions

diff --git a/appveyor.yml b/appveyor.yml
index 38a6a8e0..f58fa51c 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -15,10 +15,6 @@ environment:
       PYTHON_VERSION: "2.7.x"
       PYTHON_ARCH: "32"
 
-    - PYTHON: "C:\\Python35"
-      PYTHON_VERSION: "3.5.x"
-      PYTHON_ARCH: "32"
-
     - PYTHON: "C:\\Python36"
       PYTHON_VERSION: "3.6.x"
       PYTHON_ARCH: "32"
@@ -27,16 +23,16 @@ environment:
       PYTHON_VERSION: "3.7.x"
       PYTHON_ARCH: "32"
 
+    - PYTHON: "C:\\Python38"
+      PYTHON_VERSION: "3.8.x"
+      PYTHON_ARCH: "32"
+
     # 64 bits
 
     - PYTHON: "C:\\Python27-x64"
       PYTHON_VERSION: "2.7.x"
       PYTHON_ARCH: "64"
 
-    - PYTHON: "C:\\Python35-x64"
-      PYTHON_VERSION: "3.5.x"
-      PYTHON_ARCH: "64"
-
     - PYTHON: "C:\\Python36-x64"
       PYTHON_VERSION: "3.6.x"
       PYTHON_ARCH: "64"
@@ -45,6 +41,10 @@ environment:
       PYTHON_VERSION: "3.7.x"
       PYTHON_ARCH: "64"
 
+    - PYTHON: "C:\\Python38-x64"
+      PYTHON_VERSION: "3.8.x"
+      PYTHON_ARCH: "64"
+
 init:
   - "ECHO %PYTHON% %PYTHON_VERSION% %PYTHON_ARCH%"
 
diff --git a/docs/index.rst b/docs/index.rst
index e5e40737..dd83c6b9 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -1299,13 +1299,15 @@ Process class
     Here's an example on how to set the highest I/O priority depending on what
     platform you're on::
 
-      import psutil
-      p = psutil.Process()
-      if psutil.LINUX
-          p.ionice(psutil.IOPRIO_CLASS_RT, value=7)
-      else:  # Windows
-          p.ionice(psutil.IOPRIO_HIGH)
-      p.ionice()  # get
+      >>> import psutil
+      >>> p = psutil.Process()
+      >>> if psutil.LINUX:
+      ...     p.ionice(psutil.IOPRIO_CLASS_RT, value=7)
+      ... else:
+      ...     p.ionice(psutil.IOPRIO_HIGH)
+      ...
+      >>> p.ionice()  # get
+      pionice(ioclass=<IOPriority.IOPRIO_CLASS_RT: 1>, value=7)
 
     Availability: Linux, Windows Vista+
 
diff --git a/psutil/_psutil_bsd.c b/psutil/_psutil_bsd.c
index 74fe5922..b4264ceb 100644
--- a/psutil/_psutil_bsd.c
+++ b/psutil/_psutil_bsd.c
@@ -906,8 +906,7 @@ error:
 /*
  * define the psutil C module methods and initialize the module.
  */
-static PyMethodDef
-PsutilMethods[] = {
+static PyMethodDef mod_methods[] = {
     // --- per-process functions
 
     {"proc_oneshot_info", psutil_proc_oneshot_info, METH_VARARGS,
@@ -994,109 +993,99 @@ PsutilMethods[] = {
     {NULL, NULL, 0, NULL}
 };
 
-struct module_state {
-    PyObject *error;
-};
-
-#if PY_MAJOR_VERSION >= 3
-#define GETSTATE(m) ((struct module_state*)PyModule_GetState(m))
-#else
-#define GETSTATE(m) (&_state)
-#endif
-
 #if PY_MAJOR_VERSION >= 3
-
-static int
-psutil_bsd_traverse(PyObject *m, visitproc visit, void *arg) {
-    Py_VISIT(GETSTATE(m)->error);
-    return 0;
-}
-
-static int
-psutil_bsd_clear(PyObject *m) {
-    Py_CLEAR(GETSTATE(m)->error);
-    return 0;
-}
-
-static struct PyModuleDef
-        moduledef = {
-    PyModuleDef_HEAD_INIT,
-    "psutil_bsd",
-    NULL,
-    sizeof(struct module_state),
-    PsutilMethods,
-    NULL,
-    psutil_bsd_traverse,
-    psutil_bsd_clear,
-    NULL
-};
-
-#define INITERROR return NULL
-
-PyMODINIT_FUNC PyInit__psutil_bsd(void)
-
-#else
-#define INITERROR return
-
-void init_psutil_bsd(void)
-#endif
+    #define INITERR return NULL
+
+    static struct PyModuleDef moduledef = {
+        PyModuleDef_HEAD_INIT,
+        "_psutil_bsd",
+        NULL,
+        -1,
+        mod_methods,
+        NULL,
+        NULL,
+        NULL,
+        NULL
+    };
+
+    PyObject *PyInit__psutil_bsd(void)
+#else  /* PY_MAJOR_VERSION */
+    #define INITERR return
+
+    void init_psutil_bsd(void)
+#endif  /* PY_MAJOR_VERSION */
 {
+    PyObject *v;
 #if PY_MAJOR_VERSION >= 3
-    PyObject *module = PyModule_Create(&moduledef);
+    PyObject *mod = PyModule_Create(&moduledef);
 #else
-    PyObject *module = Py_InitModule("_psutil_bsd", PsutilMethods);
+    PyObject *mod = Py_InitModule("_psutil_bsd", mod_methods);
 #endif
-    PyModule_AddIntConstant(module, "version", PSUTIL_VERSION);
+    if (mod == NULL)
+        INITERR;
+
+    if (PyModule_AddIntConstant(mod, "version", PSUTIL_VERSION)) INITERR;
     // process status constants
 
 #ifdef PSUTIL_FREEBSD
-    PyModule_AddIntConstant(module, "SIDL", SIDL);
-    PyModule_AddIntConstant(module, "SRUN", SRUN);
-    PyModule_AddIntConstant(module, "SSLEEP", SSLEEP);
-    PyModule_AddIntConstant(module, "SSTOP", SSTOP);
-    PyModule_AddIntConstant(module, "SZOMB", SZOMB);
-    PyModule_AddIntConstant(module, "SWAIT", SWAIT);
-    PyModule_AddIntConstant(module, "SLOCK", SLOCK);
+    if (PyModule_AddIntConstant(mod, "SIDL", SIDL)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SRUN", SRUN)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SSLEEP", SSLEEP)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SSTOP", SSTOP)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SZOMB", SZOMB)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SWAIT", SWAIT)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SLOCK", SLOCK)) INITERR;
 #elif  PSUTIL_OPENBSD
-    PyModule_AddIntConstant(module, "SIDL", SIDL);
-    PyModule_AddIntConstant(module, "SRUN", SRUN);
-    PyModule_AddIntConstant(module, "SSLEEP", SSLEEP);
-    PyModule_AddIntConstant(module, "SSTOP", SSTOP);
-    PyModule_AddIntConstant(module, "SZOMB", SZOMB);  // unused
-    PyModule_AddIntConstant(module, "SDEAD", SDEAD);
-    PyModule_AddIntConstant(module, "SONPROC", SONPROC);
+    if (PyModule_AddIntConstant(mod, "SIDL", SIDL)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SRUN", SRUN)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SSLEEP", SSLEEP)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SSTOP", SSTOP)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SZOMB", SZOMB); INITERR; // unused
+    if (PyModule_AddIntConstant(mod, "SDEAD", SDEAD)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SONPROC", SONPROC)) INITERR;
 #elif defined(PSUTIL_NETBSD)
-    PyModule_AddIntConstant(module, "SIDL", LSIDL);
-    PyModule_AddIntConstant(module, "SRUN", LSRUN);
-    PyModule_AddIntConstant(module, "SSLEEP", LSSLEEP);
-    PyModule_AddIntConstant(module, "SSTOP", LSSTOP);
-    PyModule_AddIntConstant(module, "SZOMB", LSZOMB);
-    PyModule_AddIntConstant(module, "SDEAD", LSDEAD);
-    PyModule_AddIntConstant(module, "SONPROC", LSONPROC);
+    if (PyModule_AddIntConstant(mod, "SIDL", LSIDL)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SRUN", LSRUN)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SSLEEP", LSSLEEP)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SSTOP", LSSTOP)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SZOMB", LSZOMB)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SDEAD", LSDEAD)) INITERR;
+    if (PyModule_AddIntConstant(mod, "SONPROC", LSONPROC)) INITERR;
     // unique to NetBSD
-    PyModule_AddIntConstant(module, "SSUSPENDED", LSSUSPENDED);
+    if (PyModule_AddIntConstant(mod, "SSUSPENDED", LSSUSPENDED)) INITERR;
 #endif
 
     // connection status constants
-    PyModule_AddIntConstant(module, "TCPS_CLOSED", TCPS_CLOSED);
-    PyModule_AddIntConstant(module, "TCPS_CLOSING", TCPS_CLOSING);
-    PyModule_AddIntConstant(module, "TCPS_CLOSE_WAIT", TCPS_CLOSE_WAIT);
-    PyModule_AddIntConstant(module, "TCPS_LISTEN", TCPS_LISTEN);
-    PyModule_AddIntConstant(module, "TCPS_ESTABLISHED", TCPS_ESTABLISHED);
-    PyModule_AddIntConstant(module, "TCPS_SYN_SENT", TCPS_SYN_SENT);
-    PyModule_AddIntConstant(module, "TCPS_SYN_RECEIVED", TCPS_SYN_RECEIVED);
-    PyModule_AddIntConstant(module, "TCPS_FIN_WAIT_1", TCPS_FIN_WAIT_1);
-    PyModule_AddIntConstant(module, "TCPS_FIN_WAIT_2", TCPS_FIN_WAIT_2);
-    PyModule_AddIntConstant(module, "TCPS_LAST_ACK", TCPS_LAST_ACK);
-    PyModule_AddIntConstant(module, "TCPS_TIME_WAIT", TCPS_TIME_WAIT);
+    if (PyModule_AddIntConstant(mod, "TCPS_CLOSED", TCPS_CLOSED))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_CLOSING", TCPS_CLOSING))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_CLOSE_WAIT", TCPS_CLOSE_WAIT))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_LISTEN", TCPS_LISTEN))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_ESTABLISHED", TCPS_ESTABLISHED))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_SYN_SENT", TCPS_SYN_SENT))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_SYN_RECEIVED", TCPS_SYN_RECEIVED))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_FIN_WAIT_1", TCPS_FIN_WAIT_1))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_FIN_WAIT_2", TCPS_FIN_WAIT_2))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_LAST_ACK", TCPS_LAST_ACK))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_TIME_WAIT", TCPS_TIME_WAIT))
+        INITERR;
     // PSUTIL_CONN_NONE
-    PyModule_AddIntConstant(module, "PSUTIL_CONN_NONE", 128);
+    if (PyModule_AddIntConstant(mod, "PSUTIL_CONN_NONE", 128)) INITERR;
 
     psutil_setup();
 
-    if (module == NULL)
-        INITERROR;
+    if (mod == NULL)
+        INITERR;
 #if PY_MAJOR_VERSION >= 3
-    return module;
+    return mod;
 #endif
 }
diff --git a/psutil/_psutil_linux.c b/psutil/_psutil_linux.c
index 8151b75d..717723d0 100644
--- a/psutil/_psutil_linux.c
+++ b/psutil/_psutil_linux.c
@@ -537,10 +537,10 @@ error:
 
 
 /*
- * Define the psutil C module methods and initialize the module.
+ * Module init.
  */
-static PyMethodDef
-PsutilMethods[] = {
+
+static PyMethodDef mod_methods[] = {
     // --- per-process functions
 
 #ifdef PSUTIL_HAVE_IOPRIO
@@ -574,7 +574,6 @@ PsutilMethods[] = {
     {"linux_prlimit", psutil_linux_prlimit, METH_VARARGS,
      "Get or set process resource limits."},
 #endif
-
     // --- others
     {"set_testing", psutil_set_testing, METH_NOARGS,
      "Set psutil in testing mode"},
@@ -582,75 +581,51 @@ PsutilMethods[] = {
     {NULL, NULL, 0, NULL}
 };
 
-struct module_state {
-    PyObject *error;
-};
-
-#if PY_MAJOR_VERSION >= 3
-#define GETSTATE(m) ((struct module_state*)PyModule_GetState(m))
-#else
-#define GETSTATE(m) (&_state)
-#endif
 
 #if PY_MAJOR_VERSION >= 3
-
-static int
-psutil_linux_traverse(PyObject *m, visitproc visit, void *arg) {
-    Py_VISIT(GETSTATE(m)->error);
-    return 0;
-}
-
-static int
-psutil_linux_clear(PyObject *m) {
-    Py_CLEAR(GETSTATE(m)->error);
-    return 0;
-}
-
-static struct PyModuleDef
-        moduledef = {
-    PyModuleDef_HEAD_INIT,
-    "psutil_linux",
-    NULL,
-    sizeof(struct module_state),
-    PsutilMethods,
-    NULL,
-    psutil_linux_traverse,
-    psutil_linux_clear,
-    NULL
-};
-
-#define INITERROR return NULL
-
-PyMODINIT_FUNC PyInit__psutil_linux(void)
-
-#else
-#define INITERROR return
-
-void init_psutil_linux(void)
-#endif
+    #define INITERR return NULL
+
+    static struct PyModuleDef moduledef = {
+        PyModuleDef_HEAD_INIT,
+        "_psutil_linux",
+        NULL,
+        -1,
+        mod_methods,
+        NULL,
+        NULL,
+        NULL,
+        NULL
+    };
+
+    PyObject *PyInit__psutil_linux(void)
+#else  /* PY_MAJOR_VERSION */
+    #define INITERR return
+
+    void init_psutil_linux(void)
+#endif  /* PY_MAJOR_VERSION */
 {
     PyObject *v;
 #if PY_MAJOR_VERSION >= 3
-    PyObject *module = PyModule_Create(&moduledef);
+    PyObject *mod = PyModule_Create(&moduledef);
 #else
-    PyObject *module = Py_InitModule("_psutil_linux", PsutilMethods);
+    PyObject *mod = Py_InitModule("_psutil_linux", mod_methods);
 #endif
-    if (module == NULL)
-        INITERROR;
+    if (mod == NULL)
+        INITERR;
 
-    PyModule_AddIntConstant(module, "version", PSUTIL_VERSION);
+    if (PyModule_AddIntConstant(mod, "version", PSUTIL_VERSION)) INITERR;
 #if PSUTIL_HAVE_PRLIMIT
-    PyModule_AddIntConstant(module, "RLIMIT_AS", RLIMIT_AS);
-    PyModule_AddIntConstant(module, "RLIMIT_CORE", RLIMIT_CORE);
-    PyModule_AddIntConstant(module, "RLIMIT_CPU", RLIMIT_CPU);
-    PyModule_AddIntConstant(module, "RLIMIT_DATA", RLIMIT_DATA);
-    PyModule_AddIntConstant(module, "RLIMIT_FSIZE", RLIMIT_FSIZE);
-    PyModule_AddIntConstant(module, "RLIMIT_LOCKS", RLIMIT_LOCKS);
-    PyModule_AddIntConstant(module, "RLIMIT_MEMLOCK", RLIMIT_MEMLOCK);
-    PyModule_AddIntConstant(module, "RLIMIT_NOFILE", RLIMIT_NOFILE);
-    PyModule_AddIntConstant(module, "RLIMIT_NPROC", RLIMIT_NPROC);
-    PyModule_AddIntConstant(module, "RLIMIT_RSS", RLIMIT_RSS);
-    PyModule_AddIntConstant(module, "RLIMIT_STACK", RLIMIT_STACK);
+    if (PyModule_AddIntConstant(mod, "RLIMIT_AS", RLIMIT_AS)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_CORE", RLIMIT_CORE)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_CPU", RLIMIT_CPU)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_DATA", RLIMIT_DATA)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_FSIZE", RLIMIT_FSIZE)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_LOCKS", RLIMIT_LOCKS)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_MEMLOCK", RLIMIT_MEMLOCK)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_NOFILE", RLIMIT_NOFILE)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_NPROC", RLIMIT_NPROC)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_RSS", RLIMIT_RSS)) INITERR;
+    if (PyModule_AddIntConstant(mod, "RLIMIT_STACK", RLIMIT_STACK)) INITERR;
 
 #if defined(HAVE_LONG_LONG)
     if (sizeof(RLIM_INFINITY) > sizeof(long)) {
@@ -661,32 +636,33 @@ void init_psutil_linux(void)
         v = PyLong_FromLong((long) RLIM_INFINITY);
     }
     if (v) {
-        PyModule_AddObject(module, "RLIM_INFINITY", v);
+        PyModule_AddObject(mod, "RLIM_INFINITY", v);
     }
 
 #ifdef RLIMIT_MSGQUEUE
-    PyModule_AddIntConstant(module, "RLIMIT_MSGQUEUE", RLIMIT_MSGQUEUE);
+    if (PyModule_AddIntConstant(mod, "RLIMIT_MSGQUEUE", RLIMIT_MSGQUEUE)) INITERR;
 #endif
 #ifdef RLIMIT_NICE
-    PyModule_AddIntConstant(module, "RLIMIT_NICE", RLIMIT_NICE);
+    if (PyModule_AddIntConstant(mod, "RLIMIT_NICE", RLIMIT_NICE)) INITERR;
 #endif
 #ifdef RLIMIT_RTPRIO
-    PyModule_AddIntConstant(module, "RLIMIT_RTPRIO", RLIMIT_RTPRIO);
+    if (PyModule_AddIntConstant(mod, "RLIMIT_RTPRIO", RLIMIT_RTPRIO)) INITERR;
 #endif
 #ifdef RLIMIT_RTTIME
-    PyModule_AddIntConstant(module, "RLIMIT_RTTIME", RLIMIT_RTTIME);
+    if (PyModule_AddIntConstant(mod, "RLIMIT_RTTIME", RLIMIT_RTTIME)) INITERR;
 #endif
 #ifdef RLIMIT_SIGPENDING
-    PyModule_AddIntConstant(module, "RLIMIT_SIGPENDING", RLIMIT_SIGPENDING);
+    if (PyModule_AddIntConstant(mod, "RLIMIT_SIGPENDING", RLIMIT_SIGPENDING))
+        INITERR;
 #endif
 #endif
-    PyModule_AddIntConstant(module, "DUPLEX_HALF", DUPLEX_HALF);
-    PyModule_AddIntConstant(module, "DUPLEX_FULL", DUPLEX_FULL);
-    PyModule_AddIntConstant(module, "DUPLEX_UNKNOWN", DUPLEX_UNKNOWN);
+    if (PyModule_AddIntConstant(mod, "DUPLEX_HALF", DUPLEX_HALF)) INITERR;
+    if (PyModule_AddIntConstant(mod, "DUPLEX_FULL", DUPLEX_FULL)) INITERR;
+    if (PyModule_AddIntConstant(mod, "DUPLEX_UNKNOWN", DUPLEX_UNKNOWN)) INITERR;
 
-    if (module == NULL)
-        INITERROR;
+    if (mod == NULL)
+        INITERR;
 #if PY_MAJOR_VERSION >= 3
-    return module;
+    return mod;
 #endif
 }
diff --git a/psutil/_psutil_osx.c b/psutil/_psutil_osx.c
index eaf4e514..d2ca94b5 100644
--- a/psutil/_psutil_osx.c
+++ b/psutil/_psutil_osx.c
@@ -1745,8 +1745,7 @@ error:
 /*
  * define the psutil C module methods and initialize the module.
  */
-static PyMethodDef
-PsutilMethods[] = {
+static PyMethodDef mod_methods[] = {
     // --- per-process functions
 
     {"proc_kinfo_oneshot", psutil_proc_kinfo_oneshot, METH_VARARGS,
@@ -1816,96 +1815,94 @@ PsutilMethods[] = {
 };
 
 
-struct module_state {
-    PyObject *error;
-};
-
-#if PY_MAJOR_VERSION >= 3
-#define GETSTATE(m) ((struct module_state*)PyModule_GetState(m))
-#else
-#define GETSTATE(m) (&_state)
-#endif
-
 #if PY_MAJOR_VERSION >= 3
-
-static int
-psutil_osx_traverse(PyObject *m, visitproc visit, void *arg) {
-    Py_VISIT(GETSTATE(m)->error);
-    return 0;
-}
-
-static int
-psutil_osx_clear(PyObject *m) {
-    Py_CLEAR(GETSTATE(m)->error);
-    return 0;
-}
-
-
-static struct PyModuleDef moduledef = {
-    PyModuleDef_HEAD_INIT,
-    "psutil_osx",
-    NULL,
-    sizeof(struct module_state),
-    PsutilMethods,
-    NULL,
-    psutil_osx_traverse,
-    psutil_osx_clear,
-    NULL
-};
-
-#define INITERROR return NULL
-
-PyMODINIT_FUNC PyInit__psutil_osx(void)
-
-#else
-#define INITERROR return
-
-void
-init_psutil_osx(void)
-#endif
+    #define INITERR return NULL
+
+    static struct PyModuleDef moduledef = {
+        PyModuleDef_HEAD_INIT,
+        "_psutil_osx",
+        NULL,
+        -1,
+        mod_methods,
+        NULL,
+        NULL,
+        NULL,
+        NULL
+    };
+
+    PyObject *PyInit__psutil_osx(void)
+#else  /* PY_MAJOR_VERSION */
+    #define INITERR return
+
+    void init_psutil_osx(void)
+#endif  /* PY_MAJOR_VERSION */
 {
+    PyObject *v;
 #if PY_MAJOR_VERSION >= 3
-    PyObject *module = PyModule_Create(&moduledef);
+    PyObject *mod = PyModule_Create(&moduledef);
 #else
-    PyObject *module = Py_InitModule("_psutil_osx", PsutilMethods);
+    PyObject *mod = Py_InitModule("_psutil_osx", mod_methods);
 #endif
-    if (module == NULL)
-        INITERROR;
+    if (mod == NULL)
+        INITERR;
 
     if (psutil_setup() != 0)
-        INITERROR;
+        INITERR;
 
-    PyModule_AddIntConstant(module, "version", PSUTIL_VERSION);
+    if (PyModule_AddIntConstant(mod, "version", PSUTIL_VERSION))
+        INITERR;
     // process status constants, defined in:
     // http://fxr.watson.org/fxr/source/bsd/sys/proc.h?v=xnu-792.6.70#L149
-    PyModule_AddIntConstant(module, "SIDL", SIDL);
-    PyModule_AddIntConstant(module, "SRUN", SRUN);
-    PyModule_AddIntConstant(module, "SSLEEP", SSLEEP);
-    PyModule_AddIntConstant(module, "SSTOP", SSTOP);
-    PyModule_AddIntConstant(module, "SZOMB", SZOMB);
+    if (PyModule_AddIntConstant(mod, "SIDL", SIDL))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "SRUN", SRUN))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "SSLEEP", SSLEEP))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "SSTOP", SSTOP))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "SZOMB", SZOMB))
+        INITERR;
     // connection status constants
-    PyModule_AddIntConstant(module, "TCPS_CLOSED", TCPS_CLOSED);
-    PyModule_AddIntConstant(module, "TCPS_CLOSING", TCPS_CLOSING);
-    PyModule_AddIntConstant(module, "TCPS_CLOSE_WAIT", TCPS_CLOSE_WAIT);
-    PyModule_AddIntConstant(module, "TCPS_LISTEN", TCPS_LISTEN);
-    PyModule_AddIntConstant(module, "TCPS_ESTABLISHED", TCPS_ESTABLISHED);
-    PyModule_AddIntConstant(module, "TCPS_SYN_SENT", TCPS_SYN_SENT);
-    PyModule_AddIntConstant(module, "TCPS_SYN_RECEIVED", TCPS_SYN_RECEIVED);
-    PyModule_AddIntConstant(module, "TCPS_FIN_WAIT_1", TCPS_FIN_WAIT_1);
-    PyModule_AddIntConstant(module, "TCPS_FIN_WAIT_2", TCPS_FIN_WAIT_2);
-    PyModule_AddIntConstant(module, "TCPS_LAST_ACK", TCPS_LAST_ACK);
-    PyModule_AddIntConstant(module, "TCPS_TIME_WAIT", TCPS_TIME_WAIT);
-    PyModule_AddIntConstant(module, "PSUTIL_CONN_NONE", PSUTIL_CONN_NONE);
+    if (PyModule_AddIntConstant(mod, "TCPS_CLOSED", TCPS_CLOSED))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_CLOSING", TCPS_CLOSING))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_CLOSE_WAIT", TCPS_CLOSE_WAIT))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_LISTEN", TCPS_LISTEN))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_ESTABLISHED", TCPS_ESTABLISHED))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_SYN_SENT", TCPS_SYN_SENT))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_SYN_RECEIVED", TCPS_SYN_RECEIVED))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_FIN_WAIT_1", TCPS_FIN_WAIT_1))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_FIN_WAIT_2", TCPS_FIN_WAIT_2))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_LAST_ACK", TCPS_LAST_ACK))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "TCPS_TIME_WAIT", TCPS_TIME_WAIT))
+        INITERR;
+    if (PyModule_AddIntConstant(mod, "PSUTIL_CONN_NONE", PSUTIL_CONN_NONE))
+        INITERR;
 
     // Exception.
     ZombieProcessError = PyErr_NewException(
         "_psutil_osx.ZombieProcessError", NULL, NULL);
+    if (ZombieProcessError == NULL)
+        INITERR;
     Py_INCREF(ZombieProcessError);
-    PyModule_AddObject(module, "ZombieProcessError", ZombieProcessError);
+    if (PyModule_AddObject(mod, "ZombieProcessError", ZombieProcessError)) {
+        Py_DECREF(ZombieProcessError);
+        INITERR;
+    }
 
-    if (module == NULL)
-        INITERROR;
+    if (mod == NULL)
+        INITERR;
 #if PY_MAJOR_VERSION >= 3
-    return module;
+    return mod;
 #endif
 }
diff --git a/psutil/_psutil_posix.c b/psutil/_psutil_posix.c
index 5d20b21e..209e787d 100644
--- a/psutil/_psutil_posix.c
+++ b/psutil/_psutil_posix.c
@@ -618,11 +618,15 @@ psutil_net_if_duplex_speed(PyObject *self, PyObject *args) {
 #endif  // net_if_stats() macOS/BSD implementation
 
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
 /*
  * define the psutil C module methods and initialize the module.
  */
-static PyMethodDef
-PsutilMethods[] = {
+static PyMethodDef mod_methods[] = {
     {"getpriority", psutil_posix_getpriority, METH_VARARGS,
      "Return process priority"},
     {"setpriority", psutil_posix_setpriority, METH_VARARGS,
@@ -640,71 +644,45 @@ PsutilMethods[] = {
     {NULL, NULL, 0, NULL}
 };
 
-struct module_state {
-    PyObject *error;
-};
 
 #if PY_MAJOR_VERSION >= 3
-#define GETSTATE(m) ((struct module_state*)PyModule_GetState(m))
-#else
-#define GETSTATE(m) (&_state)
-#endif
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#if PY_MAJOR_VERSION >= 3
-
-static int
-psutil_posix_traverse(PyObject *m, visitproc visit, void *arg) {
-    Py_VISIT(GETSTATE(m)->error);
-    return 0;
-}
-
-
-static int
-psutil_posix_clear(PyObject *m) {
-    Py_CLEAR(GETSTATE(m)->error);
-    return 0;
-}
-
-static struct PyModuleDef moduledef = {
-    PyModuleDef_HEAD_INIT,
-    "psutil_posix",
-    NULL,
-    sizeof(struct module_state),
-    PsutilMethods,
-    NULL,
-    psutil_posix_traverse,
-    psutil_posix_clear,
-    NULL
-};
-
-#define INITERROR return NULL
-
-PyMODINIT_FUNC PyInit__psutil_posix(void)
-
-#else
-#define INITERROR return
-
-void init_psutil_posix(void)
-#endif
+    #define INITERR return NULL
+
+    static struct PyModuleDef moduledef = {
+        PyModuleDef_HEAD_INIT,
+        "_psutil_posix",
+        NULL,
+        -1,
+        mod_methods,
+        NULL,
+        NULL,
+        NULL,
+        NULL
+    };
+
+    PyObject *PyInit__psutil_posix(void)
+#else  /* PY_MAJOR_VERSION */
+    #define INITERR return
+
+    void init_psutil_posix(void)
+#endif  /* PY_MAJOR_VERSION */
 {
 #if PY_MAJOR_VERSION >= 3
-    PyObject *module = PyModule_Create(&moduledef);
+    PyObject *mod = PyModule_Create(&moduledef);
 #else
-    PyObject *module = Py_InitModule("_psutil_posix", PsutilMethods);
+    PyObject *mod = Py_InitModule("_psutil_posix", mod_methods);
 #endif
+    if (mod == NULL)
+        INITERR;
 
 #if defined(PSUTIL_BSD) || defined(PSUTIL_OSX) || defined(PSUTIL_SUNOS) || defined(PSUTIL_AIX)
-    PyModule_AddIntConstant(module, "AF_LINK", AF_LINK);
+    if (PyModule_AddIntConstant(mod, "AF_LINK", AF_LINK)) INITERR;
 #endif
 
-    if (module == NULL)
-        INITERROR;
+    if (mod == NULL)
+        INITERR;
 #if PY_MAJOR_VERSION >= 3
-    return module;
+    return mod;
 #endif
 }
 
diff --git a/scripts/internal/download_exes.py b/scripts/internal/download_exes.py
index 1b72a177..3f0be8ea 100755
--- a/scripts/internal/download_exes.py
+++ b/scripts/internal/download_exes.py
@@ -26,7 +26,7 @@ from scriptutils import printerr, exit
 
 
 BASE_URL = 'https://ci.appveyor.com/api'
-PY_VERSIONS = ['2.7', '3.5', '3.6', '3.7']
+PY_VERSIONS = ['2.7', '3.6', '3.7', '3.8']
 TIMEOUT = 30
 COLORS = True