Is this a proper use of a temporary std::string?
std::string getMyString() { return开发者_开发百科 <make a string>; }
...
HANDLE something = OpenSomething(getMyString().c_str(), ...);
I've read Guaranteed lifetime of temporary in C++ and I believe that the temporary string will live until the assignment has been evaluated, i.e. plenty long enough to make this work as expected.
Having once before run into an std::string
lifetime-related bug (can't remember what it was) I'd rather double-check...
The destructor for the temporary will not be called until after the function call returns, so what we see here is safe.
However if the called function saves the char*
and it ends up being used somehow after OpenSomething
has returned, then that's one fine dangling pointer.
Yes, this is fine. :-)
The string will be destroyed at the end of the statement, at the semi colon.
If you don't use any other argument of OpenSomthing
for returning pointer to getMyString.c_str()
everything will be OK.
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