Resolving OPatch failed with error code 73

 opatch apply
Oracle Interim Patch Installer version 12.2.0.1.8
Copyright (c) 2017, Oracle Corporation.  All rights reserved.


Oracle Home       : /u01/app/oracle/product/12.1.0.2/db_1
Central Inventory : /u01/app/oraInventory
   from           : /u01/app/oracle/product/12.1.0.2/db_1/oraInst.loc
OPatch version    : 12.2.0.1.8
OUI version       : 12.1.0.2.0
Log file location : /u01/app/oracle/product/12.1.0.2/db_1/cfgtoollogs/opatch/opatch2017-02-07_23-48-44PM_1.log

Verifying environment and performing prerequisite checks...
Prerequisite check "CheckActiveFilesAndExecutables" failed.
The details are:


Following executables are active :
/u01/app/oracle/product/12.1.0.2/db_1/bin/oracle
UtilSession failed: Prerequisite check "CheckActiveFilesAndExecutables" failed.
Log file location: /u01/app/oracle/product/12.1.0.2/db_1/cfgtoollogs/opatch/opatch2017-02-07_23-48-44PM_1.log

OPatch failed with error code 73


$ fuser /u01/app/oracle/product/12.1.0.2/db_1/bin/oracle
/u01/app/oracle/product/12.1.0.2/db_1/bin/oracle: 8291e

[oracle@bosdoradb01:WWIDOEMC] ps -ef|grep 8291
oracle    8291     1  1 00:05 ?        00:00:00 oracleWWIDOEMC (LOCAL=NO)
oracle    8861 45368  0 00:06 pts/14   00:00:00 grep 291

$ kill -9 8291

$opatch apply
Oracle Interim Patch Installer version 12.2.0.1.8
Copyright (c) 2017, Oracle Corporation.  All rights reserved.


Oracle Home       : /u01/app/oracle/product/12.1.0.2/db_1
Central Inventory : /u01/app/oraInventory
   from           : /u01/app/oracle/product/12.1.0.2/db_1/oraInst.loc
OPatch version    : 12.2.0.1.8
OUI version       : 12.1.0.2.0
Log file location : /u01/app/oracle/product/12.1.0.2/db_1/cfgtoollogs/opatch/opatch2017-02-07_23-48-44PM_1.log

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Opatch Succeed