Re: vector<string> to char*[]

From:
"Alf P. Steinbach" <alfps@start.no>
Newsgroups:
comp.lang.c++
Date:
Tue, 02 Oct 2007 16:52:57 +0200
Message-ID:
<13g4mqbp144h16e@corp.supernews.com>
* Chris ( Val ):

On Oct 2, 4:33 pm, "Alf P. Steinbach" <al...@start.no> wrote:

* Andrew Wingorodov:

i have std::vector<string> arg; for dynamic program configuration.
i need get const char* argv[]; for execv(3).
how i can make its simple?
there may be ready solutions?

   std::vector<string> arg;
   ...

   std::vector<char const*> v( arg.size() );
   for( size_t i = 0; i < v.size(); ++i ) { v[i] = arg[i].c_str(); }
   blahblah( &v[0] );


Whay go through all that when he already has what he wants
in his original vector?

const char* tmp = arg.at( n ).c_str();


Andrew wants an array of pointers to C-strings, for use as execv
argument (later down the thread I checked execv's signature and found
that there's also a const issue, and that the array should be
null-terminated, but those are just technicalities).

What you have is one pointer to a C-string.

Cheers, & hth.,

- Alf

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