orachk error : [Errno 2] No such file or directory: '/bin/oracle'.

I am using orachk version 18.4.0_20181129 on My Suse linux 12 server. Oracle RDBMS 12C R2 is installed. But no database was installed.

When I run the utility(with root and oracle user), I have this error message:  [Errno 2] No such file or directory: '/bin/oracle'.

What's wrong ?

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PATH                             : /opt/oracle/product/12.2.0/suptools/orachk
VERSION                          : 18.4.0_20181129
COLLECTIONS DATA LOCATION        : /opt/oracle/orachk/
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This computer is for [S]ingle instance database or part of a [C]luster to run RAC database [S|C] [C]: S
.

[Errno 2] No such file or directory: '/bin/oracle'