From dddca413f458fab4f3a4562329288676da9dc29c Mon Sep 17 00:00:00 2001
From: Victor Stinner <vstinner@python.org>
Date: Fri, 1 Sep 2023 17:45:04 +0200
Subject: [PATCH] gh-108765: Python.h no longer includes <unistd.h>

---
 Doc/whatsnew/3.13.rst                                 |  4 ++++
 Include/Python.h                                      | 11 +++++------
 .../2023-09-01-21-10-29.gh-issue-108765.eeXtYF.rst    |  2 ++
 Modules/grpmodule.c                                   |  3 ++-
 Modules/mmapmodule.c                                  |  1 +
 Modules/pwdmodule.c                                   |  4 +++-
 Modules/selectmodule.c                                |  1 +
 7 files changed, 18 insertions(+), 8 deletions(-)
 create mode 100644 Misc/NEWS.d/next/C API/2023-09-01-21-10-29.gh-issue-108765.eeXtYF.rst

diff --git a/Doc/whatsnew/3.13.rst b/Doc/whatsnew/3.13.rst
index d35d20ebb252936..571e37c4d50d67c 100644
--- a/Doc/whatsnew/3.13.rst
+++ b/Doc/whatsnew/3.13.rst
@@ -915,6 +915,10 @@ New Features
 Porting to Python 3.13
 ----------------------
 
+* ``Python.h`` no longer includes the ``<unistd.h>`` standard header file. If
+  needed, it should now be included explicitly.
+  (Contributed by Victor Stinner in :gh:`108765`.)
+
 Deprecated
 ----------
 
diff --git a/Include/Python.h b/Include/Python.h
index 44f0fd3ee4b56b5..603726e30e5e2e6 100644
--- a/Include/Python.h
+++ b/Include/Python.h
@@ -25,14 +25,13 @@
 #ifdef HAVE_STDDEF_H
 #  include <stddef.h>             // size_t
 #endif
-#ifndef MS_WINDOWS
-#  include <unistd.h>             // sysconf()
+#ifdef HAVE_SYS_TYPES_H
+#  include <sys/types.h>          // ssize_t
 #endif
 
-// errno.h, stdio.h, stdlib.h and string.h headers are no longer used by Python
-// headers, but kept for backward compatibility (no introduce new compiler
-// warnings). They are not included by the limited C API version 3.11 and
-// above.
+// errno.h, stdio.h, stdlib.h and string.h headers are no longer used by
+// Python, but kept for backward compatibility (avoid compiler warnings).
+// They are no longer included by limited C API version 3.11 and newer.
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
 #  include <errno.h>              // errno
 #  include <stdio.h>              // FILE*
diff --git a/Misc/NEWS.d/next/C API/2023-09-01-21-10-29.gh-issue-108765.eeXtYF.rst b/Misc/NEWS.d/next/C API/2023-09-01-21-10-29.gh-issue-108765.eeXtYF.rst
new file mode 100644
index 000000000000000..b26aab974a1f1a1
--- /dev/null
+++ b/Misc/NEWS.d/next/C API/2023-09-01-21-10-29.gh-issue-108765.eeXtYF.rst	
@@ -0,0 +1,2 @@
+``Python.h`` no longer includes the ``<unistd.h>`` standard header file. If
+needed, it should now be included explicitly. Patch by Victor Stinner.
diff --git a/Modules/grpmodule.c b/Modules/grpmodule.c
index f5709296334a8fa..20e83de84e8340f 100644
--- a/Modules/grpmodule.c
+++ b/Modules/grpmodule.c
@@ -4,7 +4,8 @@
 #include "Python.h"
 #include "posixmodule.h"
 
-#include <grp.h>
+#include <grp.h>                  // getgrgid_r()
+#include <unistd.h>               // sysconf()
 
 #include "clinic/grpmodule.c.h"
 /*[clinic input]
diff --git a/Modules/mmapmodule.c b/Modules/mmapmodule.c
index c8cd7e59dbab500..3e5c80a492f420c 100644
--- a/Modules/mmapmodule.c
+++ b/Modules/mmapmodule.c
@@ -28,6 +28,7 @@
 #include "pycore_fileutils.h"     // _Py_stat_struct
 
 #include <stddef.h>               // offsetof()
+#include <unistd.h>               // close()
 
 // to support MS_WINDOWS_SYSTEM OpenFileMappingA / CreateFileMappingA
 // need to be replaced with OpenFileMappingW / CreateFileMappingW
diff --git a/Modules/pwdmodule.c b/Modules/pwdmodule.c
index cc2e2a43893971d..f662cf63856c773 100644
--- a/Modules/pwdmodule.c
+++ b/Modules/pwdmodule.c
@@ -4,7 +4,9 @@
 #include "Python.h"
 #include "posixmodule.h"
 
-#include <pwd.h>
+#include <pwd.h>                  // getpwuid()
+#include <unistd.h>               // sysconf()
+
 
 #include "clinic/pwdmodule.c.h"
 /*[clinic input]
diff --git a/Modules/selectmodule.c b/Modules/selectmodule.c
index 4987cf0f2065c2d..367d31f265750e8 100644
--- a/Modules/selectmodule.c
+++ b/Modules/selectmodule.c
@@ -17,6 +17,7 @@
 #include "pycore_time.h"          // _PyTime_t
 
 #include <stddef.h>               // offsetof()
+#include <unistd.h>               // close()
 
 #ifdef HAVE_SYS_DEVPOLL_H
 #include <sys/resource.h>