From 0049f773f32d3fa6e93d34c2f6158952821dd7cb Mon Sep 17 00:00:00 2001 From: Nathaniel Beaver Date: Thu, 10 Sep 2015 19:42:12 -0500 Subject: [PATCH] Large footnote about history of Unix. --- README.rst | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/README.rst b/README.rst index 207d063..4eed9f3 100644 --- a/README.rst +++ b/README.rst @@ -592,6 +592,49 @@ http://www.zdnet.com/article/dear-microsoft-its-time-to-stop-using-drive-letters https://technet.microsoft.com/en-us/library/Cc938934.aspx +.. [#disk_location] + + Multics appears to be the first operating system with a root directory + and a hierarchical filesystem underneath it. + + However, the motivations for such a scheme go back further. + One of the most influential time-sharing systems, + CTSS, recognized the need for accessing files independent of their disk location. + + All files kept on the disk (and drum) are known to the + user only by name: the supervisor disk control module keeps + for each user a directory of names and corresponding track + locations on the disk. + + https://archive.org/stream/bitsavers_mitctssMAC5_3662592/MAC-TR-16_CTSStecNote_Mar65_djvu.txt + + It is desirable, from the point of view both of programming and + of disk administration, that the user have no notion of the absolute + location where his files of information are stored in the disk. Rather, + the user will refer to his files only by symbolic names and logical mode + number. + + https://archive.org/stream/bitsavers_mitctssCTS_3840198/CTSS_ProgrammersGuide_djvu.txt + + Unix was developed on relatively small disk drives, + so it was useful to be able mount drives anywhere on the filesystem. + + You know how Ken Thompson and Dennis Ritchie created Unix on a PDP-7 in 1969? + Well around 1971 they upgraded to a PDP-11 with a pair of RK05 disk packs (1.5 + megabytes each) for storage. + + When the operating system grew too big to fit on the first RK05 disk pack (their + root filesystem) they let it leak into the second one, which is where all the + user home directories lived (which is why the mount was called /usr). They + replicated all the OS directories under there (/bin, /sbin, /lib, /tmp...) and + wrote files to those new directories because their original disk was out of + space. When they got a third disk, they mounted it on /home and relocated all + the user directories to there so the OS could consume all the space on both + disks and grow to THREE WHOLE MEGABYTES (ooooh!). + + http://lists.busybox.net/pipermail/busybox/2010-December/074114.html + + --------------------- Filename restrictions ---------------------