\nA customer asked a question,\nbut as is often the case,\nthe question was much more telling than the answer.\n<\/p>\n
\nWe have an Internet Explorer plug-in which calls\n
ExitProcess<\/code>\nto force Internet Explorer to exit.\nWe found that when we do this, our plug-in does not receive a\nDLL_PROCESS_DETACH<\/code> notification.\nWhat could be preventing our plug-in from receiving the\nDLL_PROCESS_DETACH<\/code> notification?\n<\/p><\/blockquote>\n\nAs we saw some time ago when we looked at\n\nthe way processes shut down<\/a>\n(plus\n\nan important follow-up<\/a>\n\nor two<\/a>),\nall a process has to do to thwart proper delivery of\n
DLL_PROCESS_DETACH<\/code> notifications is to do something\nuntoward during shutdown, at which point the kernel\n\njust gives up and callsTerminateProcess<\/code><\/a>.\n<\/p>\n\nBut like I said, the answer is much less interesting than the question.\nWhat if the user had an unsaved email message at the time you decided\nto exit Internet Explorer?\nRecall that\n\nplug-ins are a guest in the host process; don’t go changing the carpet<\/a>.\nWhen we asked the customer why they were exiting Internet Explorer from\ntheir plug-in, we received the explanation,\n“The reason I am calling
ExitProcess<\/code>\nis that I do not know another good way to exit Internet Explorer\nfrom a plug-in.”\n<\/p>\n\nIn this case, the guest is doing far more than just changing\nthe carpet.\nThe guest called in a\n\ndemolition company<\/a>!\n<\/p>\n
\n“Why did you call the demolition company to destroy my house?”
\n“I couldn’t think of a good way to destroy your house.”\n<\/p>\n\nThe point isn’t that it’s bad to use a telephone call to hire a demolition\ncompany to destroy somebody’s house and that you should use some other\nmethod to contact them (like, say, a text message).\nThe point is that\nit’s bad to destroy somebody else’s house in the first place<\/i>.\n<\/p>\n
\nUpon further investigation, the customer was writing a test\nfor their plug-in.\nThey open Internet Explorer and navigate to a page that uses\nthe plug-in.\nWhen they are satisfied that the plug-in operated correctly,\nthey want to exit the copy of Internet Explorer in order to conclude\nthe test.\n<\/p>\n