fix typo in library; fixes dlfcn tests

src/library.js

@@ -2732,7 +2732,7 @@ LibraryManager.library = {
         flags = {{{ cDefine('O_WRONLY') }}};
       }
       flags |= {{{ cDefine('O_CREAT') }}};
-      flags |= {{{ cDefine('O_TRUNK') }}};
+      flags |= {{{ cDefine('O_TRUNC') }}};
     } else if (mode[0] == 'a') {
       if (mode.indexOf('+') != -1) {
         flags = {{{ cDefine('O_RDWR') }}};

tests/runner.py

@@ -2165,7 +2165,8 @@ if 'benchmark' not in str(sys.argv):
         open(filename, 'w').write(src)
       self.do_test(src, 'Parent global: 123.*Parent global: 456.*',
                    output_nicerizer=lambda x: x.replace('\n', '*'),
-                   post_build=add_pre_run_and_checks)
+                   post_build=add_pre_run_and_checks,
+                   extra_emscripten_args=['-H', 'libc/fcntl.h,libc/sys/unistd.h'])
       INCLUDE_FULL_LIBRARY = 0
 
     def test_dlfcn_varargs(self):