CONTENTS

    I.   LINUX REQUIREMENTS
    II.  XVIEW PROGRAMS
    III. ENDIAN ISSUES
    IV.  THORSERVER

---------------------------------------------------------------------------

I.   LINUX REQUIREMENTS

    The 4.81 Linux release for Daylight software needs the following:

      o) An Intel or Intel-Compatible based PC running Linux
         with networking.

      o) RedHat Linux 7.1 - 7.3  We have not tested RedHat 8.0 at 
         this time.

      o) An ethernet card on the PC via which the PC is networked.
         This card is absolutely necessary as its MAC address
         is used for licensing.

    At this moment there is no support for clustered Linux in this release.

---------------------------------------------------------------------------

II.  XVIEW PROGRAMS

    There are a set of xview-based graphical programs included in the 
    Daylight 4.81 distribution. To run these, xview needs to be installed
    on the client. The xview RPMs are not standard and come with the 
    extra applications disk in Deluxe versions of RedHat Linux.

    To install these RPMs, become root on your Linux machine, and then

    cd $DY_ROOT/exotic/www/linux
    rpm -U xview*rpm

    Furthermore, to use the 'Print Preview' option in the XV applications,
    one must install the 'gv' package.  The 'gv' package is included on
    the Linux RedHat distribution.

---------------------------------------------------------------------------

III. ENDIAN ISSUES

    Intel and Intel-compatible processors, unlike the SGI MIPS or 
    Sun SPARC processors, are little endian. Endianness refers to how
    the byte-ordering which the processor uses internally to store
    numbers. A big endian processor like the Sun SPARC or SGI MIPS
    processor represents a number 0x1000, as 0x1000 internally.
    A little endian processor like the Intel Pentium represents this
    as 0x0001 internally instead.  The ordering of the individual bytes
    is swapped.  This is a factor when performing datatype conversion
    and writing binary files.

    The Daylight 4.81 software has been written so that endianness is never an
    issue. Hence all Daylight Database files may be used interchangeably
    between Sun, SGI or Intel-Linux computers. The only case where endianness
    is an issue is in the clogp binary database files. You cannot use a
    fragment database binary file created on a Sun or SGI on an Intel Linux
    computer. However the textual form of the fragment files can be
    interchanged and used. When the clogp program runs the first time, it
    checks for a binary file and generates it, if not present, from the text
    file. The generated binary file is of the correct endianness for
    the system.

---------------------------------------------------------------------------

IV. THORSERVER

    The thorserver uses 32-bit file offsets and has a database file size
    limit of 2GB.  Writing data beyond the limit will cause an I/O fault
    and database corruption.  As a protective measure, the thorserver
    will deny I/O and issue a nonfatal error when a load of a TDT begins
    within 1MB of the limit.  If you want to load large (>1MB) TDT's,
    you are unprotected from writing beyond the limit.