Digital Research Inc is claiming rave reviews from hardware manufacturers for new versions of its Concurrent DOS 386 and Concurrent DOS XM multi-user, multi-tasking operating systems. C-DOS 386, launched earlier this year, now allows users to run multiple MS-DOS applications on serial terminals as well as on the main console. It can handle up to 255 tasks and up to 32 users on a 20MHz 80386 machine. Both products now offer full support for MS-DOS 3.3 utilities and single and multi-user 3.3 applications – including terminate and stay resident programs such as Sidekick. Other enhancements include the availability of up to 544Kb memory, rather than 384Kb, for each task, up to a total of 8Mb, and support for Program Information Files. There also also new commands, improved security, and support for IBM’s PS/2 range including 3.5 floppies. The new releases were developed in the UK and are claimed to offer twice the screen throughput of MS-DOS for single character input-output and seven times the performance for string input-output. Disk throughput is rated on a par with MS-DOS. C-DOS 386 and C-DOS XM will be delivered in late November through OEM customers and authorised dealer channels at UKP395 and UKP295 respectively for three users. One to 10 additional user packs for 386 and one to six user packs for XM will be UKP100. Existing users can upgrade to the new releases for UKP100.