From Sam Rushing's Medusa, via SF patch #100858: add & document

os.seteuid(), os.setegid(), os.setreuid(), os.setregid().

Doc/lib/libos.tex

@@ -181,6 +181,16 @@ calls to \function{putenv()} don't update \code{os.environ}, so it is
 actually preferable to assign to items of \code{os.environ}.  
 \end{funcdesc}
 
+\begin{funcdesc}{setegid}{egid}
+Set the current process's effective group id.
+Availability: \UNIX{}.
+\end{funcdesc}
+
+\begin{funcdesc}{seteuid}{euid}
+Set the current process's effective user id.
+Availability: \UNIX{}.
+\end{funcdesc}
+
 \begin{funcdesc}{setgid}{gid}
 Set the current process' group id.
 Availability: \UNIX{}.
@@ -199,6 +209,16 @@ for the semantics.
 Availability: \UNIX{}.
 \end{funcdesc}
 
+\begin{funcdesc}{setreuid}{ruid, euid}
+Set the current process's real and effective user ids.
+Availability: \UNIX{}.
+\end{funcdesc}
+
+\begin{funcdesc}{setregid}{rgid, egid}
+Set the current process's real and effective group ids.
+Availability: \UNIX{}.
+\end{funcdesc}
+
 \begin{funcdesc}{setsid}{}
 Calls the system call \cfunction{setsid()}.  See the \UNIX{} manual
 for the semantics.

Modules/posixmodule.c

@@ -2618,6 +2618,82 @@ posix_setuid(PyObject *self, PyObject *args)
 #endif /* HAVE_SETUID */
 
 
+#ifdef HAVE_SETEUID
+static char posix_seteuid__doc__[] =
+"seteuid(uid) -> None\n\
+Set the current process's effective user id.";
+static PyObject *
+posix_seteuid (PyObject *self, PyObject *args)
+{
+	int euid;
+	if (!PyArg_ParseTuple(args, "i", &euid)) {
+		return NULL;
+	} else if (seteuid(euid) < 0) {
+		return posix_error();
+	} else {
+		Py_INCREF(Py_None);
+		return Py_None;
+	}
+}
+#endif /* HAVE_SETEUID */
+
+#ifdef HAVE_SETEGID
+static char posix_setegid__doc__[] =
+"setegid(gid) -> None\n\
+Set the current process's effective group id.";
+static PyObject *
+posix_setegid (PyObject *self, PyObject *args)
+{
+	int egid;
+	if (!PyArg_ParseTuple(args, "i", &egid)) {
+		return NULL;
+	} else if (setegid(egid) < 0) {
+		return posix_error();
+	} else {
+		Py_INCREF(Py_None);
+		return Py_None;
+	}
+}
+#endif /* HAVE_SETEGID */
+
+#ifdef HAVE_SETREUID
+static char posix_setreuid__doc__[] =
+"seteuid(ruid, euid) -> None\n\
+Set the current process's real and effective user ids.";
+static PyObject *
+posix_setreuid (PyObject *self, PyObject *args)
+{
+	int ruid, euid;
+	if (!PyArg_ParseTuple(args, "ii", &ruid, &euid)) {
+		return NULL;
+	} else if (setreuid(ruid, euid) < 0) {
+		return posix_error();
+	} else {
+		Py_INCREF(Py_None);
+		return Py_None;
+	}
+}
+#endif /* HAVE_SETREUID */
+
+#ifdef HAVE_SETREGID
+static char posix_setregid__doc__[] =
+"setegid(rgid, egid) -> None\n\
+Set the current process's real and effective group ids.";
+static PyObject *
+posix_setregid (PyObject *self, PyObject *args)
+{
+	int rgid, egid;
+	if (!PyArg_ParseTuple(args, "ii", &rgid, &egid)) {
+		return NULL;
+	} else if (setregid(rgid, egid) < 0) {
+		return posix_error();
+	} else {
+		Py_INCREF(Py_None);
+		return Py_None;
+	}
+}
+#endif /* HAVE_SETREGID */
+
 #ifdef HAVE_SETGID
 static char posix_setgid__doc__[] =
 "setgid(gid) -> None\n\
@@ -4898,6 +4974,18 @@ static PyMethodDef posix_methods[] = {
 #ifdef HAVE_SETUID
 	{"setuid",	posix_setuid, METH_VARARGS, posix_setuid__doc__},
 #endif /* HAVE_SETUID */
+#ifdef HAVE_SETEUID
+	{"seteuid",	posix_seteuid, METH_VARARGS, posix_seteuid__doc__},
+#endif /* HAVE_SETEUID */
+#ifdef HAVE_SETEGID
+	{"setegid",	posix_setegid, METH_VARARGS, posix_setegid__doc__},
+#endif /* HAVE_SETEGID */
+#ifdef HAVE_SETREUID
+	{"setreuid",	posix_setreuid, METH_VARARGS, posix_setreuid__doc__},
+#endif /* HAVE_SETREUID */
+#ifdef HAVE_SETREGID
+	{"setregid",	posix_setregid,	METH_VARARGS, posix_setregid__doc__},
+#endif /* HAVE_SETREGID */
 #ifdef HAVE_SETGID
 	{"setgid",	posix_setgid, METH_VARARGS, posix_setgid__doc__},
 #endif /* HAVE_SETGID */

config.h.in

@@ -407,6 +407,12 @@
 /* Define if you have the select function.  */
 #undef HAVE_SELECT
 
+/* Define if you have the setegid function.  */
+#undef HAVE_SETEGID
+
+/* Define if you have the seteuid function.  */
+#undef HAVE_SETEUID
+
 /* Define if you have the setgid function.  */
 #undef HAVE_SETGID
 
@@ -419,6 +425,12 @@
 /* Define if you have the setpgrp function.  */
 #undef HAVE_SETPGRP
 
+/* Define if you have the setregid function.  */
+#undef HAVE_SETREGID
+
+/* Define if you have the setreuid function.  */
+#undef HAVE_SETREUID
+
 /* Define if you have the setsid function.  */
 #undef HAVE_SETSID
 

configure.in

@@ -822,7 +822,8 @@ AC_CHECK_FUNCS(alarm chown clock confstr ctermid ctermid_r dlopen execv \
  kill link lstat mkfifo mktime mremap \
  nice pathconf pause plock pthread_init \
  putenv readlink \
- select setgid setlocale setuid setsid setpgid setpgrp setvbuf \
+ select setegid seteuid setgid \
+ setlocale setregid setreuid setsid setpgid setpgrp setuid setvbuf \
  sigaction siginterrupt sigrelse strftime strptime symlink sysconf \
  tcgetpgrp tcsetpgrp tempnam timegm times tmpfile tmpnam tmpnam_r \
  truncate uname waitpid)