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Message-ID:	<44D21B14.2060404@scytek.de>
Date:	Thu, 03 Aug 2006 11:49:40 -0400
From:	Volker Quetschke <quetschke AT scytek DOT de>
User-Agent:	Thunderbird 1.5.0.5 (Windows/20060719)
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To:	cygwin AT cygwin DOT com
Subject:	Re: Is casting away const OK for cygwin's execvp
References:	<44D21A8E DOT 7090708 AT scytek DOT de>
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Volker Quetschke wrote:
> Basically (see the attached example program)

D'oh! I forgot the attachment.

  Volker

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#include <string>
#include <iostream>
#include <cstddef>
#include <cerrno>

using std::string;
using std::size_t;

int main() {

  const char *nargv[3];

  string arg1("echo");
  nargv[0] =3D arg1.c_str();

  string arg2("test");
  nargv[1] =3D arg2.c_str();

  nargv[2] =3D NULL;

  // Unfortunately the prototype of execvp does not like const char*,
  // actually not const char* nargv[] coming from .c_str(). So either
  // we copy everything into newly allocated variables or we force it
  // with a cast. const_cast<char * const *>() - Is this OK?
  if ( execvp(nargv[0], const_cast<char * const *>(nargv) ) < 0 ) {
    perror("Execvp error.  Aborting.");
    exit(1);=20=20=20=20=20=20=20
  }
  return 1;
}

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