passing argument to a file

i am doing C programming
how can i pass an argument from one file to another file.........i dont want to use the system command

When you say file, do you mean program?

Assuming so, then you could do
a) write out the information you want to pass between programs using a file, then read that file from your other program
b) use whatever process creation functions (say fork()/execl()) are appropriate to your OS

If you are on windows, use ShellExecute() or ShellExecuteEx().