STL string class

When you use she STL string class and the c_str() function, how does
the memory returned by c_str() get allocated and destroyed?

Thank you.

mike7411@gmail.com wrote:The memory is controlled by the string object-- after the string is
destructed you must not access the memory returned by c_str().

"Mark P" <usenet@fall2005REMOVE.fastmailCAPS.fmwrote in message
news:cBcWh.1109$ns5.542@newssvr17.news.prodigy.net ...
: mike7411@gmail.com wrote:
: When you use she STL string class and the c_str() function, how does
: the memory returned by c_str() get allocated and destroyed?
: >
: Thank you.
: >
:
: The memory is controlled by the string object
Yep.

: after the string is destructed
: you must not access the memory returned by c_str().

Not only destruction, but any operation that modifies
the string may invalidate the memory that was returned
by c_str().
I.e.:
std::string s = "Hello";
char const* p = s.c_str();
std::cout << p << std::endl; //ok
s.append('.');
std::cout << p << std::endl; // UNDEFINED BEHAVIOR


hth -Ivan
--
http://ivan.vecerina.com/contact/?subject=NG_POST <- email contact form
Brainbench MVP for C++ <http://www.brainbench.com

On Apr 21, 4:57 am, "Ivan Vecerina"
<_INVALID_use_webfo...@ivan.vecerina.comwrote:Any operation which permits modification, in fact. Calling [],
at(), begin() or end() on a non-const string, or through a
non-const reference to the string, may also invalidate the
pointer.

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