Taking backup of Control file

SQL> alter database backup controlfile to trace;

SQL> select * from V$diag_info;

                To see the trace file name.

oracle> cd /u01/app/oracle/diag/rdbms/crms/trace

oracle> ls crms_ora_2001.trc

oracle> cp crms_ora_2001.trc /home/oracle

oracle> ls

oracle> cp crms_ora_2001.trc cont.sql

oracle> vin cont.sql

                Keep the RESETLOGS and delete all the other lines from the file and save it.