diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index 035c71dcd6bf4a..46ee5fb9322819 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -2229,6 +2229,13 @@ features:
 
    Return a string representing the current working directory.
 
+.. function:: getdtablesize()
+
+   Return the maximum number of files a process can have open.
+
+   .. versionadded:: 3.14
+
+   .. availability:: Unix.
 
 .. function:: getcwdb()
 
diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py
index 1e570c757fccbc..fae2bdb9757fb4 100644
--- a/Lib/test/test_os.py
+++ b/Lib/test/test_os.py
@@ -113,6 +113,12 @@ def test_getcwd(self):
         cwd = os.getcwd()
         self.assertIsInstance(cwd, str)
 
+    @unittest.skipUnless(hasattr(os, 'getdtablesize'), 'need os.getdtablesize()')
+    def test_getdtablesize(self):
+        size = os.getdtablesize()
+        self.assertIsInstance(size, int)
+        self.assertGreaterEqual(size, 1)
+
     def test_getcwd_long_path(self):
         # bpo-37412: On Linux, PATH_MAX is usually around 4096 bytes. On
         # Windows, MAX_PATH is defined as 260 characters, but Windows supports
diff --git a/Misc/NEWS.d/next/Library/2024-09-24-14-15-34.gh-issue-83923.YunOLX.rst b/Misc/NEWS.d/next/Library/2024-09-24-14-15-34.gh-issue-83923.YunOLX.rst
new file mode 100644
index 00000000000000..0aeacf18826084
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2024-09-24-14-15-34.gh-issue-83923.YunOLX.rst
@@ -0,0 +1,2 @@
+Added :func:`os.getdtablesize` to :mod:`os` (supported only on unix-like
+systems)
diff --git a/Modules/clinic/posixmodule.c.h b/Modules/clinic/posixmodule.c.h
index 4b9dbac9af031f..79a126592c6ed6 100644
--- a/Modules/clinic/posixmodule.c.h
+++ b/Modules/clinic/posixmodule.c.h
@@ -1419,6 +1419,24 @@ os_getcwdb(PyObject *module, PyObject *Py_UNUSED(ignored))
     return os_getcwdb_impl(module);
 }
 
+PyDoc_STRVAR(os_getdtablesize__doc__,
+"getdtablesize($module, /)\n"
+"--\n"
+"\n"
+"Return the maximum number of files a process can have open.");
+
+#define OS_GETDTABLESIZE_METHODDEF      \
+    {"getdtablesize", (PyCFunction)os_getdtablesize, METH_NOARGS, os_getdtablesize__doc__},
+
+static PyObject *
+os_getdtablesize_impl(PyObject *module);
+
+static PyObject *
+os_getdtablesize(PyObject *module, PyObject *Py_UNUSED(ignored))
+{
+    return os_getdtablesize_impl(module);
+}
+
 #if defined(HAVE_LINK)
 
 PyDoc_STRVAR(os_link__doc__,
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index f24ab81cbcb77b..d44b06d350d87c 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -4218,6 +4218,22 @@ os_getcwdb_impl(PyObject *module)
     return posix_getcwd(1);
 }
 
+#ifndef MS_WINDOWS
+/*[clinic input]
+os.getdtablesize
+
+Return the maximum number of files a process can have open.
+[clinic start generated code]*/
+
+static PyObject *
+os_getdtablesize_impl(PyObject *module)
+{
+    int size;
+
+    size = getdtablesize();
+    return PyLong_FromLong(size);
+}
+#endif  /* !MS_WINDOWS */
 
 #if ((!defined(HAVE_LINK)) && defined(MS_WINDOWS))
 #define HAVE_LINK 1
@@ -16843,6 +16859,7 @@ static PyMethodDef posix_methods[] = {
     OS_CTERMID_METHODDEF
     OS_GETCWD_METHODDEF
     OS_GETCWDB_METHODDEF
+    OS_GETDTABLESIZE_METHODDEF
     OS_LINK_METHODDEF
     OS_LISTDIR_METHODDEF
     OS_LISTDRIVES_METHODDEF
diff --git a/configure b/configure
index 2c58af3eace84a..c3ca65615b5237 100755
--- a/configure
+++ b/configure
@@ -18405,6 +18405,12 @@ if test "x$ac_cv_func__getpty" = xyes
 then :
   printf "%s\n" "#define HAVE__GETPTY 1" >>confdefs.h
 
+fi
+ac_fn_c_check_func "$LINENO" "getdtablesize" "ac_cv_func_getdtablesize"
+if test "x$ac_cv_func_getdtablesize" = xyes
+then :
+  printf "%s\n" "#define HAVE_GETDTABLESIZE 1" >>confdefs.h
+
 fi
 ac_fn_c_check_func "$LINENO" "getpwent" "ac_cv_func_getpwent"
 if test "x$ac_cv_func_getpwent" = xyes
diff --git a/configure.ac b/configure.ac
index 3c1dc1cc5018d4..271a4a7fe31daa 100644
--- a/configure.ac
+++ b/configure.ac
@@ -5149,7 +5149,7 @@ AC_CHECK_FUNCS([ \
   fork fork1 fpathconf fstatat ftime ftruncate futimens futimes futimesat \
   gai_strerror getegid geteuid getgid getgrent getgrgid getgrgid_r \
   getgrnam_r getgrouplist gethostname getitimer getloadavg getlogin \
-  getpeername getpgid getpid getppid getpriority _getpty \
+  getpeername getpgid getpid getppid getpriority _getpty getdtablesize \
   getpwent getpwnam_r getpwuid getpwuid_r getresgid getresuid getrusage getsid getspent \
   getspnam getuid getwd grantpt if_nameindex initgroups kill killpg lchown linkat \
   lockf lstat lutimes madvise mbrtowc memrchr mkdirat mkfifo mkfifoat \
diff --git a/pyconfig.h.in b/pyconfig.h.in
index a5946f3547b35c..9042bc09a82c04 100644
--- a/pyconfig.h.in
+++ b/pyconfig.h.in
@@ -471,6 +471,9 @@
 /* Define this if you have flockfile(), getc_unlocked(), and funlockfile() */
 #undef HAVE_GETC_UNLOCKED
 
+/* Define to 1 if you have the `getdtablesize' function. */
+#undef HAVE_GETDTABLESIZE
+
 /* Define to 1 if you have the `getegid' function. */
 #undef HAVE_GETEGID