Theos里的config参数,MobileSubstrate和internal的区别在哪里

%config%config(X=Y);

Set a logos configuration flag.
Configuration Flags[list]
*]generator[list]
*]MobileSubstrategenerate code that uses MobileSubstrate for hooking.internalgenerate code that uses only internal Objective-C runtime methods for hooking.
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*]warnings[list]
*]nonesuppress all warningsdefaultnon-fatal warningserrormake all warnings fatal
这里的internal和mobilesubstrate机制上区别在哪里呢?好像都是生成dylib放在mobilesubstrate目录下等着加载呀?
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