From 0ff2676a2594aa6a26de7232e605640c28021f28 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 6 Oct 2025 11:13:53 +0100
Subject: [PATCH] Implement getdtablecount(3) for Darwin, from Chip Davis in
 GitHub issue 4636.

---
 compat/getdtablecount.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/compat/getdtablecount.c b/compat/getdtablecount.c
index 1f9a0aa7..e26d1c7b 100644
--- a/compat/getdtablecount.c
+++ b/compat/getdtablecount.c
@@ -18,13 +18,28 @@
 
 #include <glob.h>
 #include <unistd.h>
+#if defined(HAVE_LIBPROC_H)
+#include <libproc.h>
+#endif
 
 #include "compat.h"
 
 void fatal(const char *, ...);
 void fatalx(const char *, ...);
 
-#ifdef HAVE_PROC_PID
+#if defined(HAVE_LIBPROC_H) && defined(HAVE_PROC_PIDINFO)
+int
+getdtablecount(void)
+{
+	int	sz;
+	pid_t	pid = getpid();
+
+	sz = proc_pidinfo(pid, PROC_PIDLISTFDS, 0, NULL, 0);
+	if (sz == -1)
+		return (0);
+	return (sz / PROC_PIDLISTFD_SIZE);
+}
+#elif defined(HAVE_PROC_PID)
 int
 getdtablecount(void)
 {