;
                                 LDIR-B.COM                                   

             Size (recs) CRC   Version    Author/Latest Issue      Disk
               2k (16)   51F4  1.6        Howard Goldstein 7/90    Z3COM5

  1- Syntax  2- Notes  3- Examples of Use                                     

   LDIR-B.COM is a 'Library Directory' program which provides much more useful
information than the original LDIR.COM.  It automatically displays the name of
the library member,  its length  (in kilobytes and records),  the  compression 
method used, date of creation,  date of last modification,  and any 'comments'
provided when the member was CRUNCHed.   LDIR also displays datestamps for the
library itself.

   LDIR-B.COM should be renamed to LDIR.COM and placed on the A0: drive.
:1

   Syntax   LDIR lbrname [afn.typ]


   An optional wildcard filespec is permitted for selecting the library member
files to be shown.

   LDIR-B aborts on ^K,K,k ^X,X,x or ^C,C,c; pauses on ^S.
 
   An internal line counter  issues  a "[more]" prompt after 22 lines (byte at
104h).  Typing a space at any time sets  the line counter  to one for 'line by 
line' advance. 
:2
 LDIR-B Notes - 1/3 

   a. LDIR-B uses the middle letter of the file extension to determine whether
      a file is crunched.  If so,  a random access read of the first record of 
      the  file is  made to extract  the  real filename or possible  'comment' 
      information.  Other files are not read at all.  

   b. The display of CRC values  was  dropped  in  version 1.3 in favor of the
      modification date.  LINLEN,  as a result, was  shortened  from 21 to 19.
      Version 1.1 added minimal ZCPR3 support.  

   c. The 'length' column denotes the full number of kilobytes to  the left of
      the decimal point, followed  by a fractional part which can only be .00,
      .12, .25, .37, .50, .62, .75,  or .87 indicating  0-7 additional records
      respectively. 

   d. LDIR-B will ignore  LBR files  with .SYS attribute set, if wheel byte is
      zero.  The wheel byte  location  is  defined  by  the  byte  at 105h and 
      defaults to 3Eh.
 LDIR-B Notes - 2/3 

   e. Vs 1.6 updates (1 Jul 90, Howard Goldstein):
      - Fixed problems associated with zero-lengthh member files.  The program
        was attempting to read the first record of each member file.   Not too
        cool if the member file is empty!
      - Modified to display original file name on squeezed as well as crunched
        files.
      - Corrected usage message.
      - Removed all old commented-out code; shortened code in a few places.
      - Modified the code that reads the  LBR directory into memory to exclude
        each member's CRC.  This gets us down to 19 bytes per entry again.
      
   f. Vs 1.5 updates:
      - added capability to recognize files compressed by CRLZH
      - if file is not compressed, LDIR listing now says that it is "Stored"
      - help display changed to look more like a ZCPR3 help display
      - minor change to listing heading (HEDING:)
 LDIR-B Notes - 3/3 
   
   g. Vs 1.4 updates:
      - added display of datestamps for library itself
      - corrected bug with interpretation of crunched-file datestamp headers
      - now downcases letters of a filename which have high bits set
      - extchr replaced by crflag which will return 0ffh if file is crunched
      - changed method of determining  a file's compression.   First sector of 
      each file is now read and the  first  two bytes examined for crunched or 
      squeezed headers

   h. Version 1.3 updates:
      - added support for modification date
      - eliminated CRC in display
      - LINLEN reduced to 19
:3
 Examples of Use 

   a. B0>ldir ldirb16<cr>

Library File = LDIRB16 .LBR               

   Name           Length     Method   Cre Date   Mod Date       Comments
============   ====-======= ========  =========  =========  =================

LDIR-B  .DZC    38r   4.75k Crunched  19 Sep 89  -- --- --  (--> LDIR-B.DOC)
LDIR-B  .UZD    23r   2.87k Crunched  19 Sep 89  01 Jul 90  (--> LDIR-B.UPD)
LDIRB16 .CZM    14r   1.75k Crunched  01 Jul 90  01 Jul 90  (--> LDIRB16.COM)
LDIRB16 .ZZ0   138r  17.25k Crunched  19 Sep 89  01 Jul 90  (--> LDIRB16.Z80)
LDIRB16 .FOR     2r   0.25k  Stored   01 Jul 90  01 Jul 90  
