# Customization Points
The custom directory is an injection point for custom user configurations.
## Header `gtest.h`
### The following macros can be defined:
* `GTEST_OS_STACK_TRACE_GETTER_` - The name of an implementation of
`OsStackTraceGetterInterface`.
* `GTEST_CUSTOM_TEMPDIR_FUNCTION_` - An override for `testing::TempDir()`. See
`testing::TempDir` for semantics and signature.
## Header `gtest-port.h`
The following macros can be defined:
### Logging:
* `GTEST_LOG_(severity)`
* `GTEST_CHECK_(condition)`
* Functions `LogToStderr()` and `FlushInfoLog()` have to be provided too.
### Threading:
* `GTEST_HAS_NOTIFICATION_` - Enabled if Notification is already provided.
* `GTEST_HAS_MUTEX_AND_THREAD_LOCAL_` - Enabled if `Mutex` and `ThreadLocal`
are already provided. Must also provide `GTEST_DECLARE_STATIC_MUTEX_(mutex)`
and `GTEST_DEFINE_STATIC_MUTEX_(mutex)`
* `GTEST_EXCLUSIVE_LOCK_REQUIRED_(locks)`
* `GTEST_LOCK_EXCLUDED_(locks)`
### Underlying library support features
* `GTEST_HAS_CXXABI_H_`
### Exporting API symbols:
* `GTEST_API_` - Specifier for exported symbols.
## Header `gtest-printers.h`
* See documentation at `gtest/gtest-printers.h` for details on how to define a
custom printer.