Try to set a write lock on a write lock(Denied), set a write lock on unlocked file (Allowed)

Slave0: Create a file, write data, close it
Slave0: Open the file for read\write
Slave1: Open the file for read\write
In cycle:
Slave0: Set a write lock on 1 byte
Slave0: Read one byte of data
In cycle:
Slave1: Try to set a write lock on the same peace of data( Denied)
Slave1: Wait 0.0001sec
Slave0: Unlock all file
Slave1: Set a write lock on the released piece of a file