Mateusz' DOS Routines (MDR) is a C library that contain a variety of routines to ease the development of real mode DOS applications.
These routines are mostly targeted at the Open Watcom compiler, but might work with other C compilers as well.
All the routines have been created by Mateusz Viste and are published under the terms of the MIT license.
Documentation, when present, is contained within header (*.H) files.
MDR files can also be fetched through svn:
svn co http://svn.osdn.net/svnroot/mdr mdr