diff --git a/cmake.config/iwyu/mapping.imp b/cmake.config/iwyu/mapping.imp
index 47f4274265..4cb2898c73 100644
--- a/cmake.config/iwyu/mapping.imp
+++ b/cmake.config/iwyu/mapping.imp
@@ -121,7 +121,6 @@
   { include: [ '"os/shell.h.generated.h"', private, '"nvim/os/shell.h"', public ] },
   { include: [ '"os/signal.h.generated.h"', private, '"nvim/os/signal.h"', public ] },
   { include: [ '"os/time.h.generated.h"', private, '"nvim/os/time.h"', public ] },
-  { include: [ '"os_unix.h.generated.h"', private, '"nvim/os_unix.h"', public ] },
   { include: [ '"path.h.generated.h"', private, '"nvim/path.h"', public ] },
   { include: [ '"plines.h.generated.h"', private, '"nvim/plines.h"', public ] },
   { include: [ '"popupmenu.h.generated.h"', private, '"nvim/popupmenu.h"', public ] },
diff --git a/src/nvim/fileio.c b/src/nvim/fileio.c
index 6bad91e959..5e7c7cb943 100644
--- a/src/nvim/fileio.c
+++ b/src/nvim/fileio.c
@@ -52,7 +52,6 @@
 #include "nvim/os/input.h"
 #include "nvim/os/os.h"
 #include "nvim/os/time.h"
-#include "nvim/os_unix.h"
 #include "nvim/path.h"
 #include "nvim/pos.h"
 #include "nvim/regexp.h"
diff --git a/src/nvim/os/fs.c b/src/nvim/os/fs.c
index 8c4fee58b1..4906dd0df2 100644
--- a/src/nvim/os/fs.c
+++ b/src/nvim/os/fs.c
@@ -779,6 +779,38 @@ int os_setperm(const char *const name, int perm)
   return (r == kLibuvSuccess ? OK : FAIL);
 }
 
+#if defined(HAVE_ACL)
+# ifdef HAVE_SYS_ACL_H
+#  include <sys/acl.h>
+# endif
+# ifdef HAVE_SYS_ACCESS_H
+#  include <sys/access.h>
+# endif
+
+// Return a pointer to the ACL of file "fname" in allocated memory.
+// Return NULL if the ACL is not available for whatever reason.
+vim_acl_T os_get_acl(const char_u *fname)
+{
+  vim_acl_T ret = NULL;
+  return ret;
+}
+
+// Set the ACL of file "fname" to "acl" (unless it's NULL).
+void os_set_acl(const char_u *fname, vim_acl_T aclent)
+{
+  if (aclent == NULL) {
+    return;
+  }
+}
+
+void os_free_acl(vim_acl_T aclent)
+{
+  if (aclent == NULL) {
+    return;
+  }
+}
+#endif
+
 #ifdef UNIX
 /// Checks if the current user owns a file.
 ///
diff --git a/src/nvim/os_unix.c b/src/nvim/os_unix.c
deleted file mode 100644
index 074a8b7936..0000000000
--- a/src/nvim/os_unix.c
+++ /dev/null
@@ -1,42 +0,0 @@
-// This is an open source non-commercial project. Dear PVS-Studio, please check
-// it. PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
-
-#include "nvim/os/os_defs.h"
-#include "nvim/os_unix.h"
-#include "nvim/types.h"
-
-#ifdef INCLUDE_GENERATED_DECLARATIONS
-# include "os_unix.c.generated.h"  // IWYU pragma: export
-#endif
-
-#if defined(HAVE_ACL)
-# ifdef HAVE_SYS_ACL_H
-#  include <sys/acl.h>
-# endif
-# ifdef HAVE_SYS_ACCESS_H
-#  include <sys/access.h>
-# endif
-
-// Return a pointer to the ACL of file "fname" in allocated memory.
-// Return NULL if the ACL is not available for whatever reason.
-vim_acl_T os_get_acl(const char_u *fname)
-{
-  vim_acl_T ret = NULL;
-  return ret;
-}
-
-// Set the ACL of file "fname" to "acl" (unless it's NULL).
-void os_set_acl(const char_u *fname, vim_acl_T aclent)
-{
-  if (aclent == NULL) {
-    return;
-  }
-}
-
-void os_free_acl(vim_acl_T aclent)
-{
-  if (aclent == NULL) {
-    return;
-  }
-}
-#endif
diff --git a/src/nvim/os_unix.h b/src/nvim/os_unix.h
deleted file mode 100644
index 31430ee23a..0000000000
--- a/src/nvim/os_unix.h
+++ /dev/null
@@ -1,10 +0,0 @@
-#ifndef NVIM_OS_UNIX_H
-#define NVIM_OS_UNIX_H
-
-#include "nvim/os/shell.h"
-#include "nvim/types.h"
-
-#ifdef INCLUDE_GENERATED_DECLARATIONS
-# include "os_unix.h.generated.h"
-#endif
-#endif  // NVIM_OS_UNIX_H
diff --git a/src/nvim/undo.c b/src/nvim/undo.c
index 0777d1309d..9cbe5d5d9e 100644
--- a/src/nvim/undo.c
+++ b/src/nvim/undo.c
@@ -116,7 +116,6 @@
 #include "nvim/os/os.h"
 #include "nvim/os/os_defs.h"
 #include "nvim/os/time.h"
-#include "nvim/os_unix.h"
 #include "nvim/path.h"
 #include "nvim/pos.h"
 #include "nvim/screen.h"