Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!uwm.edu!linac!mp.cs.niu.edu!ux1.cso.uiuc.edu!midway!gsbsun!valley From: valley@gsbsun.uchicago.edu (Doug Dougherty) Newsgroups: comp.sys.ibm.pc.misc Subject: Re: When can you SYS a disk not originally formatted with /S? Message-ID: <1991May4.154438.26496@midway.uchicago.edu> Date: 4 May 91 15:44:38 GMT References: <1991May3.191723.24131@midway.uchicago.edu> <91123.230837JXS118@psuvm.psu.edu> Sender: news@midway.uchicago.edu (NewsMistress) Organization: University of Chicago Lines: 23 JXS118@psuvm.psu.edu (Jeff Siegel) writes: (Stuff deleted) >3) The file IBMBIO.COM is the first file to occupy the data space. The >clusters of the file must be in order and must be contiguous. >4) The file IBMDOS.COM is on the disk somewhere. Can be anywhere, and doesn't >have to be contigiuous. >Thus a disk is 'sys'able if the first two directory slots are empty and if >there is room to put IBMBIO.COM down as the first file in the data space. Well, that's a start, but it tells me things I already knew. The basic point is this: Early versions of DOS required that the slots (for the two system files) be allocated and reserved at format time. Hence, if a disk was formatted w/o /S, you couldn't SYS it. Period. You would have to reformat it with /S, in order to make it bootable. Somewhere along the way, this changed. Now, you can SYS a disk as long as it is empty. (Of course, I'm sure other restrictions apply, and your mileage may vary) -- (Another fine mess brought to you by valley@gsbsun.uchicago.edu)