How much space used in each transaction log file

Is there a way to know how much space is free in each transaction log file of the same database?

Example:

A database with 3, 1GB files for transaction log: A, B and C created in this sequence.

From what I have read, since SQL Server 2005 writes to a single transaction log only, I guess if the transaction log is using 2.5GB than A and B are full and B is only half full. Is this correct?

Thanks.Transaction log usage is the same for sql2k/5. It writes sequentially. To determine the used space for tran log, do this:

dbcc sqlperf(logspace)