how to pass a file name to my program ?

Dear all , I need to pass the file name to my program to get the tokens in it, my program still in early stage , have a look and coment please

I have the 'code_file' . which should be passed
And the 'bin' file which holds the reserved words and the grammars as the following

bin.txt

Code:

---


[RESERVED_WORDS]
NEWJOB
CONST
VARIABLE
BEGINB
ENDB
EXIT


[GRAMMAR]

---

Code:

---

#include < iostream.h>
  #include < fstream.h >
  #include < string.h  >
 

//using namespace std;


 ifstream input("c:\\compiler_test\\code_file.txt"); // the code text file
 ifstream bin_file("c:\\compiler_test\\bin.txt"); // compiler information file


// array holds the reserved words
typedef char string[20] ;
string reserved[20];



// separators list
// 10 the end line , 32 the space char
// you can add new separator symbol here
char sep_list[] = { 10,32, '.', ',', ';', ',', '+', '-', '='};
const int is_Sep(char) ;  // returns 1 if in the sep_list ,0 if not




// scanning functions
void get_Reserved();
void scan_bin();



//
//
//
int main()
{ 
        char d;
  if ( !bin_file.is_open() )
            cout << "the file couldn't be opened !" ;
        else cout << "the file is opend successfully !" ;

 
scan_bin();  // get all the information needed


 
// printing the RESERVED_WORDS list
cout << endl;
for(int i =0 ; i < 20 ; i++)
cout << reserved[i] << endl;

        cout << "\n \n press any key to exit";
        cin.get();

        return 0; // main end
}
//----------------------------------------------------------
//__________________________________________________________

void scan_bin(){
// this function scans the bin file to get all the informations
 int row=0;
 int col=0;
 char ch;
 char temp[20];
 

  while(!bin_file.eof())
  { bin_file.get(ch);

        while ( !is_Sep(ch) & !input.eof() & ch!=-1)
        {  temp[col++]=ch;                 
                bin_file.get(ch); }
            temp[col] = '\0';

                if(!strcmp(temp , "[RESERVED_WORDS]"))
                  get_Reserved();  // calling the reserved words scanning function
  }

}



void get_Reserved()
{// the tokens scanned here should be under RESERVED_WORDS tag
 // if new tag bracket faced , the function will exit       
 int row=0;
 int col=0;
 char ch;    // temporary for scanned symbol
 char temp[20]; // temporary for scanned word
 
  while(!bin_file.eof())
  { bin_file.get(ch);
                while ( !is_Sep(ch) & !input.eof() & ch!=-1)
                                {  if( ch=='[' | ch==']')
                                                return;
                                        temp[col++]=ch;                 
                                        bin_file.get(ch); }

                temp[col] = '\0';
                strcpy(reserved[row] , temp);  // copying the word into the list
                col=0;
                row++;
                                   
 
  }

}


//--------------
const int is_Sep(char c)
{  //This function checks the symbol c if in the separator
  // using sizeof for flexible add in the array
        for(int i=0 ; i<sizeof(sep_list) ; i++)
                if(c==sep_list[i])
                        return 1; // in the list
 return 0; // not in the list
}

---

thanks

Pass the file name into main() via a command line argument.

Code:

---

int main(int argc, char* argv[])
{
    if(argc > 1)
        std::cout << "File name: " << argv[1] << std::endl;
    else
        std::cout << "You need to pass in a file name to the program via the command line\n";
}

---

thanks , but if did this , I can't change the file name in the input object in the run time , I dont know ??

>but if did this , I can't change the file name in the input object in the run time
Why not?

How can the program open many files , in many paths ?

please note that the input object should be global , and the path should be assigned in runtime