fix error

lib/process_shared/posix/libc.rb

@@ -31,8 +31,11 @@ module ProcessShared
           File.exists?(File.join(path, helper))
         end
 
-        ffi_lib File.join(path, helper)
-        
+        if  defined?(Truffle)
+          ffi_lib(File.join(::Truffle::Boot.toolchain_paths(:LD_LIBRARY_PATH), 'libgraalvm-llvm.so.1'), File.join(path, helper))
+        else
+          ffi_lib File.join(path, helper)
+        end      
         [:o_rdwr,
          :o_creat,
          :o_excl,