2 files changed, 4 insertions, 1 deletions
diff --git a/Misc/NEWS b/Misc/NEWS
index 3899da5..ceab576 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -91,6 +91,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #17964: Fix os.sysconf(): the return type of the C sysconf() function
+  is long, not int.
+
 - Fix typos in the multiprocessing module.
 
 - Issue #17754: Make ctypes.util.find_library() independent of the locale.
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index bf57138..cb72bf0 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -9550,7 +9550,7 @@ posix_sysconf(PyObject *self, PyObject *args)
     int name;
 
     if (PyArg_ParseTuple(args, "O&:sysconf", conv_sysconf_confname, &name)) {
-        int value;
+        long value;
 
         errno = 0;
         value = sysconf(name);