enter the file name by keyboard instead of command line arguments?

[high12]

Actually the below program is for Dispersal Algorithm called Rabin-IDA; this algorithm divided the data into N pieces and then recombine it from M pieces (such that M<N).

Thus, the below program needs command line arguments,which entering by Project properties/Debugging. this argument is file name, where the program performing spitted the file into N files, and then recombine it from M divided files, and put it on another file which should also passing its name as argument .

Now my question is, How can i make this program enter the file name by keyboard??(i mean enter the files name by user from screen not as command line arguments)
In another word, How I can exchange

argc == 3

and

argc == 2

to enter file name ? i mean what i should do to in

rabin.split(argv[1])

to pass my file name by use keyboard not Project properties/Debugging?)

the below code is just the main function of program, and the whole of it in this link (http://www.juancamilocorena.com/home/projects) Information Dispersal Algorithms Rabin-IDA.

#include "include.h"

void __cdecl _tmain(int argc, TCHAR *argv[])
{
DWORD ini=GetTickCount();
try
{
if( argc == 3 ) //recombine
{
RabinIDA rabin=RabinIDA(17,10);
long long size=GetFileSize(argv[1]);
int f[]={0,2,3,5,6,8,9,11,14,15};
rabin.recombine(argv[1],
f,
argv[2],
size);
}
else if(argc == 2)
{
RabinIDA rabin=RabinIDA(17,10);
rabin.split(argv[1]);
}
else
{
printf("Error. To split a file pass a parameter with the file to be splitted\n");
printf("To recombine the file give the name of the original file and the output file\n");
printf("The name of the file is used to get the size of the original file only, in a production\n");
printf("environment the length of the original file and the id of the share must be stored along with the share");
return;
}
printf("%d\n",GetTickCount()-ini);
}
catch (int)
{
PrintLastError(_T("MAIN CATCH"));
}
}

i know i should use getline() function but how exchange argv[] ?