How to use mount system call to mount nfs exported file syst

[bs_madhu]

How to use mount system call to mount nfs exported file system. When I use mount call as mentioned below ,I am getting invalid arguments error.
mount("7.80.201.232:/usr/test124", "/usr/test","nfs",MS_MGC_VAL,"rw,async") .
If I use mount executable it works.
mount -t nfs 7.80.201.232:/usr/test124 /usr/test .works

[c.s.prakash]

i am too getting the same erro when i mount nfs thru mount but it works when
i mount the local file system thru mount system call