ANSI-fication of the sources, convert to 4-space indents.

Use PyArg_ParseTuple() to get better error messages.
Add docstrings all around.

Modules/grpmodule.c

@@ -15,8 +15,9 @@ redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 #include <sys/types.h>
 #include <grp.h>
 
-static PyObject *mkgrent(p)
-	struct group *p;
+
+static PyObject *
+mkgrent(struct group *p)
 {
     PyObject *v, *w;
     char **member;
@@ -47,12 +48,12 @@ static PyObject *mkgrent(p)
     return v;
 }
 
-static PyObject *grp_getgrgid(self, args)
-	PyObject *self, *args;
+static PyObject *
+grp_getgrgid(PyObject *self, PyObject *args)
 {
     int gid;
     struct group *p;
-	if (!PyArg_Parse((args),"i",(&gid)))
+    if (!PyArg_ParseTuple(args, "i:getgrgid", &gid))
         return NULL;
     if ((p = getgrgid(gid)) == NULL) {
         PyErr_SetString(PyExc_KeyError, "getgrgid(): gid not found");
@@ -61,12 +62,12 @@ static PyObject *grp_getgrgid(self, args)
     return mkgrent(p);
 }
 
-static PyObject *grp_getgrnam(self, args)
-	PyObject *self, *args;
+static PyObject *
+grp_getgrnam(PyObject *self, PyObject *args)
 {
     char *name;
     struct group *p;
-	if (!PyArg_Parse((args),"s",(&name)))
+    if (!PyArg_ParseTuple(args, "s:getgrnam", &name))
         return NULL;
     if ((p = getgrnam(name)) == NULL) {
         PyErr_SetString(PyExc_KeyError, "getgrnam(): name not found");
@@ -75,12 +76,13 @@ static PyObject *grp_getgrnam(self, args)
     return mkgrent(p);
 }
 
-static PyObject *grp_getgrall(self, args)
-	PyObject *self, *args;
+static PyObject *
+grp_getgrall(PyObject *self, PyObject *args)
 {
     PyObject *d;
     struct group *p;
-	if (!PyArg_NoArgs(args))
+
+    if (!PyArg_ParseTuple(args, ":getgrall"))
         return NULL;
     if ((d = PyList_New(0)) == NULL)
         return NULL;
@@ -98,14 +100,39 @@ static PyObject *grp_getgrall(self, args)
 }
 
 static PyMethodDef grp_methods[] = {
-	{"getgrgid",	grp_getgrgid},
-	{"getgrnam",	grp_getgrnam},
-	{"getgrall",	grp_getgrall},
+    {"getgrgid",	grp_getgrgid,	METH_VARARGS,
+     "getgrgid(id) -> tuple\n\
+Return the group database entry for the given numeric group ID.  If\n\
+id is not valid, raise KeyError."},
+    {"getgrnam",	grp_getgrnam,	METH_VARARGS,
+     "getgrnam(name) -> tuple\n\
+Return the group database entry for the given group name.  If\n\
+name is not valid, raise KeyError."},
+    {"getgrall",	grp_getgrall,	METH_VARARGS,
+     "getgrall() -> list of tuples\n\
+Return a list of all available group entries, in arbitrary order."},
     {NULL,		NULL}		/* sentinel */
 };
 
+static char grp__doc__[] =
+"Access to the Unix group database.\n\
+\n\
+Group entries are reported as 4-tuples containing the following fields\n\
+from the group database, in order:\n\
+\n\
+  name   - name of the group\n\
+  passwd - group password (encrypted); often empty\n\
+  gid    - numeric ID of the group\n\
+  mem    - list of members\n\
+\n\
+The gid is an integer, name and password are strings.  (Note that most\n\
+users are not explicitly listed as members of the groups they are in\n\
+according to the password database.  Check both databases to get\n\
+complete membership information.)";
+
+
 DL_EXPORT(void)
 initgrp()
 {
-	Py_InitModule("grp", grp_methods);
+    Py_InitModule3("grp", grp_methods, grp__doc__);
 }