oraInventory Location & oraInst.loc on Windows , Linux , Unix

oraInventory Location & oraInst.loc on Windows , Linux , Unix

Oracle Software (Database, OID, HTTP Server, Forms & Report, Discoverer …) installation issues are logged under oraInventory/logs/[filename].log, but how to identify oraInventory location on system ?
Oracle Inventory Pointer oraInst.loc (registry variable inst_loc for windows)  determines oraInventory location

oraInventory location in windows : INST_LOC - “c:\program files\Oracle\Inventory“

oraInventory default location in Linux, AIX : Directory mentioned in /etc/oraInst.loc

oraInventory default location in Solaris: Directory mentioned in /var/opt/oracle / oraInst.loc

oraInventory default location in HP OpenVMS: Directory under sys$login 

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To find INST_LOC registry variable in windows : Start > Run > regedit > HKLM > Software > Oracle
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