Preliminary documentation for LBRDISK (CP/M 2.2 version)




                         Jim Lopushinsky

                          March 5, 1984


What is LBRDISK?
----------------

     LBRDISK  is  an  extension of the CP/M 2.2 BDOS  (RSX)  that 
allows  you to treat libraries and archives as a  logical  drive.  
For  example,  to squeeze and collect into a library a collection 
of text files you might do the following:

B>CREATE TEXT.LBR          <--- creates an empty library
Allow how many entries: 12 <--- 12 files. 
B>LBRDISK C:=TEXT          <--- allocate drive C to TEXT.LBR
B>NSQ C:=*.TXT             <--- squeeze all text files into TEXT.LBR

It  doesn't matter if the assigned drive actually exists or  not.  
All  transient  programs (including the CCP) have access  to  the 
newly created drive.

Are there any restrictions?
---------------------------

     Yes.  LBRDISK allows modifications to the library drive only 
if  one  library or archive is allocated.   If more than  one  is 
allocated,  the library drive becomes Read-only,  and will return 
appropriate CP/M errors if an attempt is made to write,  erase or 
rename a file on the library drive.

     There  must  not  be more than one open output file  on  the 
library  drive.   Programs  must  close any  output  file  before 
opening another.  There are no restrictions on the number of open 
input files.

     Libraries and archives are sequential files.  It is strongly 
recomended  to erase a file and re-make it before writing to  it.  
Writing  to an existing file is allowed.   However,  the  records 
replace existing records in the old file,  and if writing  occurs 
past  the  end of the file,  the next member will  be  clobbered.  
Making a new file causes output records to be appended to the end 
of  the library.   Random write is allowed,  but the program must 
not leave any "holes" in the file.

     As  far as I can tell,  all the common utilities operate  as 
expected.

     Editors should not be used, unless you are positive that the 
editor maintains only one output file at a time.


What are the programs?
----------------------

     There are two utilities associated with LBRDISK:

1.  CREATE - to create an empty library or archive.  This utility 
will run under CP/M 2.2 as well as CP/M 3.

2.   SETRSX  - loads the RSX manager just below  the  CCP.   This 
utility  must be executed prior to using LBRDISK.   It is  loaded 
once only, and remains active through warm boots.


How do I use LBRDISK?
---------------------

     Here is the syntax:

A>LBRDISK
     Entering  LBRDISK with no command tail will remove the  last 
active Lbrdisk RSX from memory.  If there is more than one active 
Lbrdisk, only the last one loaded is removed.

A>LBRDISK C1:=B5:CASM,C:TEXT
     Drive  C user 1 will be allocated to CASM on B5 and TEXT  on 
C0.

B>LBRDISK C:=*,1:=A1:JRT*,2:=2:CASM,LASM
     Drive C will be assigned to the following:
     C0 = all libraries and archives on B0
     C1 = all libraries and archives on A1 beginning with JRT
     C2 = CASM on B2 and LASM on B0

In the above two examples, drive C becomes read-only.

B>LBRDISK D:=TEST
     D0 will be assigned to TEST on B0.   Since only one  library 
was specified, drive D becomes read-write.  If we now execute the 
following:

B>LBRDISK C:=1:TESTA
     A  second  library  drive is created.   C0 is  now  all  the 
members  from  TESTA on B1.   There is nothing stopping you  from 
using NSWP to copy members back and forth between the 2 libraries 
and/or archives!

B>CREATE TEST.LBR
Allow how many entries: 6
     This creates an empty TEST.LBR file with room for a  maximum 
of 6 members.

B>CREATE TEST.ARC
     This creates an empty TEST.ARC and TEST.DIR file.

B>SETRSX
     This  command  must be executed before  using  LBRDISK.   If 
executed a second time,  it removes the RSX manager,  and any LBR 
RSXs below it.


Please  make  any  bug reports and/or comments to  the  SYSOP  at 
Meadowlark RCP/M (403) 484-5981 @ 300/1200 baud.