not.hDuplicate

Hello glasgow-haskell-users, my program contaions several forkOSed threads and at one moment one thread gives to another handle of open file. i need to read some data from this file. how can i accomplish this? if i use hDuplicate, then both handles will share the same file pointer, so threads will mess each other. are there some way to duplicate handle with creating separate file pointer, or to get filename from the Handle, or (preferable) to block another thread's on attempt to access the same handle until i done with it and return to old file pointer? -- Best regards, Bulat mailto:bulatz@HotPOP.com