<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:16px"><div style="" class=""><span style="" class="">> Johnny Billquist <bqt@softjar.se> wrote:<br style=""><br style="" class="">> One thing Cutler did, which you do not find in the predecessors are ACPs.<br style="" class=""><br style="" class="">If so, he may have a claim to inventing (a hint at) a microkernel concept. ;-)<br style="" class=""><br style="" class="">Ironically, while ACPs made a lot of sense in a PDP-11 world due to the constraints in address space and kernel memory size, but rolling ACP idea over to VMS was much less productive (since these constraints were gone), and eventually F11 ACP was replaced with in-process XQP.<br style="" class=""><br style="" class="">I am wondering though if FUSE developers ever heard of ACPs or reinvented the concept from scratch.<br style="" class="">At least
http://en.wikipedia.org/wiki/Filesystem_in_Userspace<br style="" class="">claims that "The idea of a filesystem driver living in userspace was originally developed in 1995".<br style="" class=""><br style="" class="">It is also curious that ACPs (whether in traditional form or XQP form) allowed to do one thing that Unix/Linux interface still does not -- opening files as an asynchronous operation -- but </span><span style="" class=""><span style="" class="">ironically </span>the chief utility of this capability is mainly for web servers which were not invented back then yet.<br style="" class=""><br style="" class="">P.S. To come think of it, my very first project as a salaried software developer (more akin to commercial enterprise of Tom Sawyer in fence painting business) at ca. 1984 involved writing an ACP-like structure... not for a file system, but for a graphics card, on RSX.<br style="" class=""></span></div></div></body></html>