--log_level

`--log_level`

This argument controls the level of test runner output. The values are cumulative, with each increase in log level including all messages at lower levels. By default, only errors are reported. See test runner log for more information on the log.

Value	Meaning
`nothing`	Do not report any information.
`fatal_error`	Report all user or system fatal errors, such as memory access violation.
`system_error`	Report system non-fatal errors, such as timeout or floating-point exception.
`cpp_exception`	Report uncaught C++ exceptions.
`error` (default)	Report test failures.
`warning`	Report test warnings.
`message`	Report test messages; see `BOOST_TEST_MESSAGE`.
`test_suite`	Report entering and leaving every test case and test suite.
`success`	Report all successful assertions.
`all`	Report everything.

Environment variable: BOOST_TEST_LOG_LEVEL