LU301.OBJ is a patched version of Gary's LU300.OBJ The FIXes relate to the !!bloody!! liberties that the BDS-C libraries take with CP/M calls. Apparently someone at Digital Research back in version 1.4 said that the L register on return from a CP/M BDOS call should contain a copy of A, ( and apparently B contain a copy of E) or something similar. The effect of this is that anybody who writes a DOS that doesnt follow that redundancy falls foul of this poorly documented 'feature' of CP/M 2.2 In particular BDS-C tests the HL register contents on return from system calls (instead of the more common A register). This does not work with some CP/Ms (such as that on the DEC RAINBOW), or in IOS. In order to use this latest version of Gary's LU program I have painstakingly gone through the object code and removed the HL usages one by one. LU301.OBJ is the result. If you have any trouble with LU on YOUR system try this version. If it works let me know. I will coordinate the replies to Leor, who hopefully might be persuaded to eliminate the problem in the next version of the BDC compiler. If LU300.OBJ already works on your system then LU301 offers nothing to you. ....Trevor Marshall, SYSOP, Thousand Oaks Technical RCP/M (RIOS). (805) 492 5472 or voice (805) 492 3693