ACE has been ported and tested on a wide range of OS platforms including Windows (i.e., WinNT 3.5.x, 4.x, 2000, Embedded NT, XP, Win95/98, and WinCE using MSVC++, Borland C++ Builder, and IBM's Visual Age on 32- and 64-bit Intel and Alpha platforms), Mac OS X, most versions of UNIX (e.g., Solaris on SPARC and Intel, SGI IRIX 5.x and 6.x, DG/UX, HP-UX 10.x, and 11.x, Tru64UNIX 3.x and 4.x, AIX 3.x, 4.x, 5.x, DG/UX, UnixWare, SCO, and freely available UNIX implementations, such as Debian Linux 2.x, RedHat Linux 5.2, 6.x, 7.x, 8x, and 9.x, as well as the various Enterprise editions, SUSE Linux 8.1 and 9.2, Timesys Linux, FreeBSD, and NetBSD), real-time operating systems (e.g., LynxOS, VxWorks, ChorusOS, QnX Neutrino, RTEMS, OS9, and PSoS), OpenVMS, MVS OpenEdition, and CRAY UNICOS. A single source tree is used for all these platforms. There is also a Java version of ACE.