Conversion from std::string to char *, is there a better way?

From: Julie (julie_at_nospam.com)
Date: 06/10/04 

Date: Thu, 10 Jun 2004 10:48:33 -0700

I'm re-evaluating the way that I convert from a std::string to char *.
(Requirement: the source is a std::string, the usable contents are char *)

Here is what I've come up with:

#include <string>
#include <vector>
#include <cstring>

  // presume s from somewhere, such as:
  std::string s = "<initial value>";

  std::vector<char> v(s.length() + 1);
  std::strcpy(&v[0], s.c_str());
  char * c = &v[0];
  // use c, where a char * is _specifically_ required
  s = c;

The above:
 - doesn't use any pointers that must be manually deallocated
 - is 100% portable(?)
 - is 100% conformant(?)

I've seen Bjarne's similar implementation, but it uses new char * instead of
vector (obviously written before the STL was adopted).

auto_ptr<char> in place of vector<char> doesn't work because it doesn't handle
arrays.

Does anyone have comments on the above, specifically as to its suitability for
the requirements defined?

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