diff --git a/bin/dig/dig.c b/bin/dig/dig.c
index fbcd9737d7..69cc7e0bf2 100644
--- a/bin/dig/dig.c
+++ b/bin/dig/dig.c
@@ -19,6 +19,7 @@
 
 #include <isc/app.h>
 #include <isc/attributes.h>
+#include <isc/dir.h>
 #include <isc/netaddr.h>
 #include <isc/parseint.h>
 #include <isc/platform.h>
diff --git a/bin/dnssec/dnssec-cds.c b/bin/dnssec/dnssec-cds.c
index 4da36c5f9e..b58e62d78e 100644
--- a/bin/dnssec/dnssec-cds.c
+++ b/bin/dnssec/dnssec-cds.c
@@ -24,6 +24,7 @@
 #include <isc/attributes.h>
 #include <isc/buffer.h>
 #include <isc/commandline.h>
+#include <isc/dir.h>
 #include <isc/file.h>
 #include <isc/hash.h>
 #include <isc/mem.h>
diff --git a/bin/dnssec/dnssec-dsfromkey.c b/bin/dnssec/dnssec-dsfromkey.c
index 618ab03cdc..3d60729983 100644
--- a/bin/dnssec/dnssec-dsfromkey.c
+++ b/bin/dnssec/dnssec-dsfromkey.c
@@ -18,6 +18,7 @@
 #include <isc/attributes.h>
 #include <isc/buffer.h>
 #include <isc/commandline.h>
+#include <isc/dir.h>
 #include <isc/hash.h>
 #include <isc/mem.h>
 #include <isc/print.h>
diff --git a/bin/dnssec/dnssec-signzone.c b/bin/dnssec/dnssec-signzone.c
index d1ee147277..4329fe7f0a 100644
--- a/bin/dnssec/dnssec-signzone.c
+++ b/bin/dnssec/dnssec-signzone.c
@@ -36,6 +36,7 @@
 #include <isc/attributes.h>
 #include <isc/base32.h>
 #include <isc/commandline.h>
+#include <isc/dir.h>
 #include <isc/event.h>
 #include <isc/file.h>
 #include <isc/hash.h>
diff --git a/bin/named/geoip.c b/bin/named/geoip.c
index f38b200505..e949d209e9 100644
--- a/bin/named/geoip.c
+++ b/bin/named/geoip.c
@@ -15,6 +15,7 @@
 #include <maxminddb.h>
 #endif /* if defined(HAVE_GEOIP2) */
 
+#include <isc/dir.h>
 #include <isc/print.h>
 #include <isc/string.h>
 #include <isc/util.h>
diff --git a/fuzz/fuzz.h b/fuzz/fuzz.h
index 15b2592f7c..abbce372ed 100644
--- a/fuzz/fuzz.h
+++ b/fuzz/fuzz.h
@@ -13,6 +13,7 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include <isc/dir.h>
 #include <isc/lang.h>
 #include <isc/mem.h>
 #include <isc/once.h>
diff --git a/lib/bind9/check.c b/lib/bind9/check.c
index 50ed64b48e..a67f68a356 100644
--- a/lib/bind9/check.c
+++ b/lib/bind9/check.c
@@ -23,6 +23,7 @@
 #include <isc/aes.h>
 #include <isc/base64.h>
 #include <isc/buffer.h>
+#include <isc/dir.h>
 #include <isc/file.h>
 #include <isc/hex.h>
 #include <isc/log.h>
diff --git a/lib/dns/journal.c b/lib/dns/journal.c
index 36ebbd1718..567692e7a4 100644
--- a/lib/dns/journal.c
+++ b/lib/dns/journal.c
@@ -15,6 +15,7 @@
 #include <stdlib.h>
 #include <unistd.h>
 
+#include <isc/dir.h>
 #include <isc/file.h>
 #include <isc/mem.h>
 #include <isc/print.h>
diff --git a/lib/dns/tests/geoip_test.c b/lib/dns/tests/geoip_test.c
index b7020ccc1d..810f8378a6 100644
--- a/lib/dns/tests/geoip_test.c
+++ b/lib/dns/tests/geoip_test.c
@@ -24,6 +24,7 @@
 #include <cmocka.h>
 #include <maxminddb.h>
 
+#include <isc/dir.h>
 #include <isc/print.h>
 #include <isc/string.h>
 #include <isc/types.h>
diff --git a/lib/dns/view.c b/lib/dns/view.c
index dacb875a53..5de3108d45 100644
--- a/lib/dns/view.c
+++ b/lib/dns/view.c
@@ -20,6 +20,7 @@
 #endif /* ifdef HAVE_LMDB */
 
 #include <isc/atomic.h>
+#include <isc/dir.h>
 #include <isc/file.h>
 #include <isc/hash.h>
 #include <isc/lex.h>
diff --git a/lib/isc/include/isc/dir.h b/lib/isc/include/isc/dir.h
index f42ebe6959..8473f9bba8 100644
--- a/lib/isc/include/isc/dir.h
+++ b/lib/isc/include/isc/dir.h
@@ -9,12 +9,12 @@
  * information regarding copyright ownership.
  */
 
-#ifndef ISC_DIR_H
-#define ISC_DIR_H 1
+#pragma once
 
 /*! \file */
 
 #include <dirent.h>
+#include <limits.h>
 
 #include <isc/lang.h>
 #include <isc/platform.h>
@@ -22,6 +22,14 @@
 
 #include <sys/types.h> /* Required on some systems. */
 
+#ifndef NAME_MAX
+#define NAME_MAX 256
+#endif
+
+#ifndef PATH_MAX
+#define PATH_MAX 1024
+#endif
+
 /*% Directory Entry */
 typedef struct isc_direntry {
 	char	     name[NAME_MAX];
@@ -69,5 +77,3 @@ isc_dir_createunique(char *templet);
  */
 
 ISC_LANG_ENDDECLS
-
-#endif /* ISC_DIR_H */
diff --git a/lib/isc/include/isc/platform.h.in b/lib/isc/include/isc/platform.h.in
index 73dbe80836..ce32692f03 100644
--- a/lib/isc/include/isc/platform.h.in
+++ b/lib/isc/include/isc/platform.h.in
@@ -18,24 +18,6 @@
  ***** Platform-dependent defines.
  *****/
 
-/***
- *** System limitations
- ***/
-
-#include <limits.h>
-
-#ifndef NAME_MAX
-#define NAME_MAX 256
-#endif
-
-#ifndef PATH_MAX
-#define PATH_MAX 1024
-#endif
-
-#ifndef IOV_MAX
-#define IOV_MAX 1024
-#endif
-
 /*
  * Tell emacs to use C mode for this file.
  *
diff --git a/lib/ns/tests/plugin_test.c b/lib/ns/tests/plugin_test.c
index bf0af1cfd5..0e6296c601 100644
--- a/lib/ns/tests/plugin_test.c
+++ b/lib/ns/tests/plugin_test.c
@@ -24,6 +24,7 @@
 #include <cmocka.h>
 
 #include <isc/attributes.h>
+#include <isc/dir.h>
 #include <isc/mem.h>
 #include <isc/platform.h>
 #include <isc/result.h>