Under the Hood

• Darwin

  • open source operating system consisting of non-graphical components of OS X

  • Mach

    • heavily modified form of Mach version 3

    • kernel developed at Carnegie-Mellon

    • designed for modularity, and to develop version of UNIX free of AT&T licensing

    • provides multitasking, multithreading, virtual memory, memory protection, interprocess messaging, and device access

    • Tip: virtual memory contained in dynamically resized file, located at /var/vm/swapfile*

  • BSD UNIX

    • 4.4BSD

    • based on code from the open-source BSD flavors: FreeBSD, OpenBSD, NetBSD (FreeBSD is the future reference platform)

    • Tip: startup scripts located in /System/Library/StartupItems/

    • Tip: enter ">console" in loginwindow for command-line login

    • Tip: hold down "V" key during bootup to see textual startup messages

  • Filesystem Support

    • Local: HFS+, HFS, UFS, ISO 9660, UDF

      • See the paper by Wilfredo Sanchez for discussion of compatibility issues

    • Network: AFP, NFS

      • no obvious way to set up NFS

      • CIFS by installing Samba

  • Network Services

    • TELNET, FTP, etc. (all the usual inetd stuff)

    • SSH

      • Enable on boot by entering SSHSERVER=-YES- into /etc/hostconfig

    • Mail (Sendmail)

      • Can install POP and IMAP servers

    • Web (Apache)

    • DNS (BIND)

  • NetInfo

    • directory service

• Quartz

  • drawing engine based on PostScript imaging model, uses PDF as internal format

  • true WYSIWYG

  • no native remote windowing capability

  • only major UNIX variant not to use the X Window system as its native graphics engine

    • at least two versions of X Windows now exist, one free (XFree86) and one commercial (Tenon)

  • Aqua (the GUI)

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Copyright © 1999-2001 Leon Towns-von Stauber. All rights reserved.