If two or more users run tests on the same OpenTP1 system, the trace information may be mixed and the test results may be difficult to verify. To prevent this risk, a test user ID is set for each user of the online tester. The online tester assigns output files for trace information and MCF send messages, using the test user IDs.

Set a unique test user ID for each user, subject to the following conditions:

Environment variable	Value attribute	Number of characters
DCUTOKEY	1-byte alphanumerics (a-z, A-Z, and 0-9)	Up to 4

Setting test user IDs means that trace files and MCF send message files can be created and used by each test user ID.

Test user IDs are obtained at the following times:

• At UAP startup by the OpenTP1 dcsvstart command
• At specification of the dcsvstart command in the user service configuration definition
• At a service request to an SPP by the online tester's utosppsvc or utoxsppsvc command
• At a service request to an MHP by the online tester's utomhpsvc command

The test user ID may be assumed as _uto when the OpenTP1 system is restarted after forced termination (-f option in the dcsvstop command) or after a system shutdown during normal termination processing of a test UAP. A message is output, reporting that the system was restarted with the assumed test user ID. If necessary, re-enter the dcsvstart command to restart the OpenTP1 system after UAP termination.