Add version

Author: grantjenks

selectlib.c

@@ -1,5 +1,3 @@
-/* selectlib.c */
-    
 #include <Python.h>
 #include <listobject.h>
 #include <stdlib.h>
@@ -9,6 +7,10 @@
 #define PY_SSIZE_T_CLEAN
 #endif
 
+#ifndef SELECTLIB_VERSION
+#define SELECTLIB_VERSION "1.0.0"
+#endif
+
 /*
    Helper function that compares two PyObject*s using the < operator.
    Returns 1 if a < b, 0 if not, or -1 if an error occurred.
@@ -214,5 +216,13 @@ static struct PyModuleDef selectlibmodule = {
 PyMODINIT_FUNC
 PyInit_selectlib(void)
 {
-    return PyModule_Create(&selectlibmodule);
+    PyObject *m = PyModule_Create(&selectlibmodule);
+    if (m == NULL)
+        return NULL;
+    /* Add the module's version constant */
+    if (PyModule_AddStringConstant(m, "__version__", SELECTLIB_VERSION) < 0) {
+        Py_DECREF(m);
+        return NULL;
+    }
+    return m;
 }