c++ - Does std::move on std::string garantee that .c_str() returns same result? -

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i want provide zero-copy, move based api. want move string thread thread b. ideologically seems move shall able pass\move data instance new instance b minimal none copy operations (mainly addresses). data data pointers copied no new instance (constructed via move). std::move on std::string garantee .c_str() returns same result on instance before move , instance created via move constructor?

no,

but if needed, option put string in std::unique_ptr. typically not rely on c_str() value more local scope.

example, on request:

#include <iostream> #include <string> #include <memory>  int main() {     std::string ss("hello");     auto u_str = std::make_unique<std::string>(ss);     std::cout << u_str->c_str() <<std::endl;     std::cout << *u_str <<std::endl;     return 0; }

if don't have make_unique (new in c++14). 

auto u_str = std::unique_ptr<std::string>(new std::string(ss));

or copy whole implementation proposal s.t.l.:

ideone example on how that


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