int main(int argc, char* argv[])
{
  printf("path = %s\n", argv[0]);
}

C:\Temp> test
path = C:\Temp\test.exe

C:\Temp> tEsT
path = C:\Temp\tEsT.exe

C:\Temp> call test
path = test

C:\Temp> call ..\temp\.\.\test
path = ..\temp\.\.\test