init variable in c++ -


i encountered strange problem, @ times, @ no. when read data file insert map, data read file attached struct type traderecord , insert map. when init object order_tmp don't assign value 0 have field in traderecord don't have in file assign junk value c++ compiler.

//struct traderecord struct traderecord   {    int               order;            // order ticket    int               login;            // owner's login    char              symbol[12];       // security    int               digits;           // security precision    int               cmd;              // trade command    int               volume;           // volume    //---    __time32_t        open_time;        // open time    int               state;            // reserved    double            open_price;       // open price    double            sl,tp;            // stop loss & take profit    __time32_t        close_time;       // close time    int               gw_volume;        // gateway order volume    __time32_t        expiration;       // pending order's expiration time    char              reason;           // trade reason    char              conv_reserv[3];   // reserved fields    double            conv_rates[2];    // convertation rates profit currency group deposit currency                                        // (first element-for open time, second element-for close time)    double            commission;       // commission    double            commission_agent; // agent commission    double            storage;          // order swaps    double            close_price;      // close price    double            profit;           // profit    double            taxes;            // taxes    int               magic;            // special value used client experts    char              comment[32];      // comment    int               gw_order;         // gateway order ticket    int               activation;       // used mt manager    short             gw_open_price;    // gateway order price deviation (pips) order open price    short             gw_close_price;   // gateway order price deviation (pips) order close price    double            margin_rate;      // margin convertation rate (rate of convertation margin currency deposit one)    __time32_t        timestamp;        // timestamp    int               api_data[4];      // api usage    traderecord *__ptr32 next;          // internal data   };  //code read data file         while (file.good())         {             std::getline(file, line_str);             boost::split(fields, line_str, boost::is_any_of(k_delimiter));              // line don't enough data             if (fields.size() < k_line_fields)             {                 log(debug) << m_log_tag << "ignore line " << line << ", not enough data: " << line_str;                 line++;                 continue;             }              log(debug) << m_log_tag << "data line " << line << ": " << line_str;              traderecord order_tmp;              order_tmp.login                = atoi(fields[0].c_str());             order_tmp.order                = atoi(fields[1].c_str());             strncpy_s(order_tmp.symbol, _countof(order_tmp.symbol), fields[2].c_str(), _truncate);             order_tmp.volume               = atoi(fields[3].c_str());             order_tmp.cmd                  = atoi(fields[4].c_str());             order_tmp.open_price           = atof(fields[5].c_str());             order_tmp.margin_rate          = atof(fields[6].c_str());             order_tmp.open_time            = atoi(fields[7].c_str());              list_open_order.insert(std::make_pair(order_tmp.order, order_tmp));             log(debug) << std::fixed << "for test, read open order: " << order_tmp.order << ", swap=" << order_tmp.storage;             line++;         }

like can see, in traderecord has many fields in file not enough, c++ auto assign value these(-92559631349317830000000000000000000000000000000000000000000000.000000 this)

but not understand why problem when not because normal

you should not use variable without giving default value. in c++ (unlike other programming languages java) not auto-initialize variables. in case, integer in stack value of whatever random data there.


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