multiprocessing/utils.close_fds also has to work for fake (negative)

graalpython _multiprocessing file descriptors

Author: tomasstupka

graalpython/lib-python/3/multiprocessing/util.py

@@ -18,6 +18,10 @@
 
 from . import process
 
+# Begin Truffle change
+from _multiprocessing import _close
+# End Truffle change
+
 __all__ = [
     'sub_debug', 'debug', 'info', 'sub_warning', 'get_logger',
     'log_to_stderr', 'get_temp_dir', 'register_after_fork',
@@ -461,7 +465,13 @@ def spawnv_passfds(path, args, passfds):
 def close_fds(*fds):
     """Close each file descriptor given as an argument"""
     for fd in fds:
-        os.close(fd)
+        # Begin Truffle change
+        #os.close(fd)
+        if fd < 0:
+            _close(fd)
+        else:
+            os.close(fd)
+        # End Truffle change
 
 
 def _cleanup_tests():