<div dir="ltr"><div>I'm writing a linux kernel filesystem driver for Project Oberon disk images and I'm wondering how best to interpret the Date field in the FileDesc record. </div><div><br></div><div>It looks to me like the Files module just puts the latest Kernel.Clock() value in there when the file is written.</div><div><br></div><div>System.Mod sets the date value like this:</div><div><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">dt </span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">:=</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> </span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">((((</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">yr</span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">*</span><span class="gmail-pl-c1" style="box-sizing:border-box;color:rgb(0,92,197);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">16</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> </span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">+</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> mo</span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">)*</span><span class="gmail-pl-c1" style="box-sizing:border-box;color:rgb(0,92,197);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">32</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> </span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">+</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> day</span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">)*</span><span class="gmail-pl-c1" style="box-sizing:border-box;color:rgb(0,92,197);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">32</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> </span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">+</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> hr</span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">)*</span><span class="gmail-pl-c1" style="box-sizing:border-box;color:rgb(0,92,197);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">64</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> </span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">+</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> min</span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">)*</span><span class="gmail-pl-c1" style="box-sizing:border-box;color:rgb(0,92,197);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">64</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> </span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">+</span><span style="color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre"> sec</span><span class="gmail-pl-smi" style="box-sizing:border-box;color:rgb(36,41,46);font-family:SFMono-Regular,Consolas,"Liberation Mono",Menlo,monospace;font-size:12px;white-space:pre">;</span><br></div><div dir="ltr"><br></div><div>It looks to me like the above formula leaves 6 bits for the year, which means it ranges from 0 to 63.</div><div><br></div><div>Now I know that the FPGA doesn't actually have a real time clock and I think the time is always actually zero unless you set it to something else. I don't think it gets updated from the system millisecond timer either.</div><div><br></div><div>I'm just wondering if historically that year value that goes in a file header has a base year  or other meaning. Without something like that the maximum year is "63" which is a long time ago!</div><div><br></div><div>I'd like to put something meaningful in this field when I move files in and out of Linux.</div><div><br></div><div>Anybody have a good idea? Should I just make it based on Jan 1 1970 like Unix, in which case it rolls over in 2033?</div><div><br></div><div>Am I over-thinking this? </div><div><br></div><div>Chuck</div><div dir="ltr"><br></div><br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>
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