Signal handling and diagnostic framework considerations:
the OCI diagnostic framework installs signal handlers that may impact any signal handling that you use in your application. You can disable OCI signal handling by setting
DIAG_SIGHANDLER_ENABLED=FALSE
in the sqlnet.ora file. Refer to “Fault Diagnosability in OCI” in Oracle Call Interface Programmer’s Guide for information.
Please try to configure this environment variable in sqlnet.ora file