RTEMSLicense

From RTEMSWiki

RTEMS is licensed under a modified version of the GNU General Public License (GPL). The modification places no restrictions on the applications which use RTEMS but protects the interests of those who work on RTEMS.

The TCP/IP network stack included with RTEMS is a port of the FreeBSD network stack and is licensed under different terms that also does not place restrictions on the application.

For complete licensing information on RTEMS, see http://www.rtems.com/license.