boost/tools/common/time_string.hpp

// ---- time_string: thin wrapper around std::strftime    -------- //
//
//            Copyright Gennaro Prota 2006
//
// Distributed under the Boost Software License, Version 1.0.
//    (See accompanying file LICENSE_1_0.txt or copy at
//          http://www.boost.org/LICENSE_1_0.txt)
//
// ------------------------------------------------------------------
//
// $Id$

#ifndef BOOST_TIME_STRING_HPP_GP_20060731
#define BOOST_TIME_STRING_HPP_GP_20060731

#include <string>
#include <ctime>

namespace boost {

// Many of the boost tools just need a quick way to obtain
// a formatted "run date" string or similar. This is one.
//
// In case of failure false is returned and result is
// unchanged.
//
inline
bool time_string(std::string & result
               , const std::string & format = "%X UTC, %A %d %B %Y")
{
    // give up qualifying names and using std::size_t,
    // to avoid including "config.hpp"
    using namespace std;

    const int sz = 256;
    char buffer [ sz ] = { 0 };
    const time_t no_cal_time ( -1 );
    time_t tod;

    const bool ok =
        time ( &tod ) != no_cal_time
     && strftime( buffer, sz, format.c_str(), gmtime( &tod ) ) != 0
        ;

    if (ok)
        result = buffer;

    return ok;
}

}

#endif // include guard