User`s guide
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KwikNet Virtual File System
Sector Size
Virtual files are stored in character arrays which, for lack of a better term, are called
sector arrays. By default, the maximum size of a sector array is 32,768 bytes. The
...SSIZE keyword can be used to change the maximum size of these sector arrays.
...SSIZE NBYTES
Parameter NBYTES defines the maximum number of bytes which the VFS Generator will
insert into a sector array. The upper limit for this parameter is 32,768 bytes. Setting this
parameter to a small value will increase the memory footprint of your Virtual File System
unless most of your virtual files are small.
You should only have to use this directive to overcome array size limitations imposed by
some very primitive C compilers. The number of bytes stored in a sector array has no
correlation with the sector size on any real disk drive.
The sector size, once adjusted, applies to the virtual files which are subsequently
specified using the ...IN keyword. Although the sector size can be adjusted as often as
you wish, there is rarely a need to do so.
Multiple Volumes
In rare cases, you may wish to build an application that uses more than one Virtual File
System volume. This process is described in Chapter 7.4.
Each Virtual File System volume is given a volume name. The default volume name
used by the VFS Generator is kvfs_primary. Each additional volume must be given a
unique volume name using the ...VOLUME keyword.
...VOLUME VOLNAME
Parameter VOLNAME is the volume name to be given to the Virtual File System created
from the VFS Definition File containing the ...VOLUME directive. All volume names
must be unique. Your C compiler must be able to create a public variable using the
volume name as the name of the variable.