Late last month, Tenon Intersystems Inc, Santa Barbara, California started delivering the first copies of MachTen, its novel approach to making the simple Apple Computer Inc Macintosh a cheap workstation. MachTen puts the Mach operating system on the Mac, anything from a Classic upwards, enabling it to continue running off-the-shelf Apple applications while simultaneously running Unix programs and bringing Unix multitasking, Internet communications and an Network File System-based distributed file system to the MacOS. Files are stored in Mac form so the Unix and Mac programs can share data. The product was originally expected in the first quarter, but Tenon decided to polish the apple and add a few more features, such as a full Macintosh Finder interface and the ability to click on Unix before bringing it to market. MachTen is actually Berkeley 4.3 BSD on a Carnegie Mellon Mach 2.5 foundation, in the process of going Mach 3. Installing it, there is no need to partition the disk, add new device drivers or disturb any existing Mac operations. It is a development as well as an applications environ ment. The start-up that built it is currently selling direct and talking to possible distrib utors. Prime sites are those with both Unix workstations and Macs in place. Expectations are that sales will number 100 to 200 units a month in the autumn, 300 a month by year’s end. Cost is $600 for a workstation licence with un limited terminals but no upgrade provisions one from the other. Planned enhancements include server and client X Window support in the fourth quarter this year, and Mac System 7.0 compatibility in the first quarter of 1992.