I programming in c++ and I need help.

I made one program that should run other program, but i got one problem
Program unable to run program if it running directly from other folder.
t.ex.

program located in folder
c:\windows\progs\myprog.exe

I starting it in command line from root C:\

and program showing that path not found

but when i opening c:\windows\progs\ and then running program, so it works.

....
how can I make program to find folder that it was running from. (programs local folder and run other program from this folder)