Try fixing build on meson of readdir dirent args.

configure.ac

@@ -119,6 +119,7 @@ AC_CHECK_FUNC([fcntl],,    AC_MSG_ERROR("Could not find fcntl"))
 AC_CHECK_FUNC([setlocale],,AC_MSG_ERROR("Could not find setlocale"))
 AC_CHECK_FUNC([atexit],,   AC_MSG_ERROR("Could not find atexit in c library"))
 AC_CHECK_FUNC([glob],,     AC_MSG_ERROR("Could not find glob in c library"))
+AC_CHECK_FUNC([readdir],,  AC_MSG_ERROR("Could not find readdir in c library"))
 
 AC_CHECK_HEADER([math.h],, AC_MSG_ERROR("Could not find math.h header file"))
 AC_SEARCH_LIBS([floor],[m],,      AC_MSG_ERROR("Could not find floor in math library"))

meson.build

@@ -12,6 +12,7 @@ c_compiler = meson.get_compiler('c')
 add_project_arguments(
     '-I@0@'.format(meson.build_root()),
     '-I@0@'.format(join_paths(meson.source_root(), 'include')),
+    '-D_DEFAULT_SOURCE=1',
     language: 'c'
 )
 

source/dialogs/filebrowser.c

@@ -31,6 +31,9 @@
 #include <gmodule.h>
 #include <gio/gio.h>
 
+#include <sys/types.h>
+#include <dirent.h>
+
 #include "mode.h"
 #include "helper.h"
 #include "mode-private.h"