will taking the address of the first element of a string break COW strings?
in [C++]
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From: Brendan on 6 Jul 2010 11:20 With vectors, you can take the address of the first element in order to pass the underlying data to API's that take char*'s like so: vector<char> v(BUF_SIZE); // for some function: void write_to_buf(char* buf, size_t buf_len) write_to_buf(&v[0], BUF_SIZE); With std::strings I've always been leery of doing the same thing since I know that some std::string implementations, gcc's in particular, are Copy On Write. To make this safe, a COW string str would have to make a copy when you do a str[index] if there is more than one reference to the underlying string. Does the standard require this to be safe? Thanks, Brendan -- [ See http://www.gotw.ca/resources/clcm.htm for info about ] [ comp.lang.c++.moderated. First time posters: Do this! ] |