.. SPDX-License-Identifier: BSD-3-Clause Copyright(c) 2010-2014 Intel Corporation. **Part 2: Development Environment** Source Organization =================== This section describes the organization of sources in the DPDK framework. Libraries --------- Libraries are located in subdirectories of ``dpdk/lib``. By convention a library refers to any code that provides an API to an application. Typically, it generates an archive file (``.a``), but a kernel module would also go in the same directory. Drivers ------- Drivers are special libraries which provide poll-mode driver implementations for devices: either hardware devices or pseudo/virtual devices. They are contained in the *drivers* subdirectory, classified by type, and each compiles to a library with the format ``librte_X_Y.a`` where ``X`` is the device class name and ``Y`` is the driver name. .. note:: Several of the ``driver/net`` directories contain a ``base`` sub-directory. The ``base`` directory generally contains code the shouldn't be modified directly by the user. Any enhancements should be done via the ``X_osdep.c`` and/or ``X_osdep.h`` files in that directory. Refer to the local README in the base directories for driver specific instructions. Applications ------------ Applications are source files that contain a ``main()`` function. They are located in the ``dpdk/app`` and ``dpdk/examples`` directories. The app directory contains sample applications that are used to test DPDK (such as autotests) or the Poll Mode Drivers (test-pmd). The examples directory contains :doc:`Sample applications<../sample_app_ug/index>` that show how libraries can be used.