OPatch failed with error code 41

How to fix “OPatch failed with error code 41”
 orFollowing executables are active :/u01/app/oracle/product/12.1.0/dbhome_1/lib/libclntsh.so.12.1

Symptom:

[oracle@gc12c 17027533]$ $ORACLE_HOME/OPatch/opatch apply
Oracle Interim Patch Installer version 12.1.0.1.0
Copyright (c) 2012, Oracle Corporation.  All rights reserved.


Oracle Home       : /u01/app/oracle/product/12.1.0/dbhome_1
Central Inventory : /u01/app/oraInventory
   from           : /u01/app/oracle/product/12.1.0/dbhome_1/oraInst.loc
OPatch version    : 12.1.0.1.0
OUI version       : 12.1.0.1.0
Log file location : /u01/app/oracle/product/12.1.0/dbhome_1/cfgtoollogs/opatch/17027533_Dec_02_2013_18_09_09/apply2013-12-02_18-09-09PM_1.log

Applying interim patch '17027533' to OH '/u01/app/oracle/product/12.1.0/dbhome_1'
Verifying environment and performing prerequisite checks...
Prerequisite check "CheckActiveFilesAndExecutables" failed.
The details are:

Following executables are active :
/u01/app/oracle/product/12.1.0/dbhome_1/lib/libclntsh.so.12.1
Log file location: /u01/app/oracle/product/12.1.0/dbhome_1/cfgtoollogs/opatch/17027533_Dec_02_2013_18_09_09/apply2013-12-02_18-09-09PM_1.log
Recommended actions: OPatch needs to modify files which are being used by some processes.

OPatch failed with error code 41

Fix: find out which process is currently use it, and kill it

[oracle@gc12c 17027533]$ fuser /u01/app/oracle/product/12.1.0/dbhome_1/lib/libclntsh.so.12.1
/u01/app/oracle/product/12.1.0/dbhome_1/lib/libclntsh.so.12.1:  4063m
[oracle@gc12c 17027533]$ ps up 4063
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
oracle    4063  0.0  0.2  81256 11400 pts/2    S+   11:41   0:02 adrci
[oracle@gc12c 17027533]$ kill 4063
[oracle@gc12c 17027533]$ ps up 4063
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
[oracle@gc12c 17027533]$  fuser /u01/app/oracle/product/12.1.0/dbhome_1/lib/libclntsh.so.12.1