home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Collection of Tools & Utilities
/
Collection of Tools and Utilities.iso
/
dskut
/
prune22.zip
/
PRUNE.DOC
< prev
next >
Wrap
Text File
|
1992-03-31
|
4KB
|
85 lines
Program Name: PRUNE (PRUNE.EXE)
Version: 2.1 September, 1990
Function: Clear out unallocated bytes at the end of a file.
Requirements: 64K, DOS 2.0 or later.
Command Syntax: prune filespec...filespec
prune /s filespec...
prune /f "fill value" filespec...
prune /u filespec...
"filespec" may contain drive and path specifiers, as well
as wildcards (* and ?). If the "/s" option is given, all
subdirectories will be searched for matching files. The
fill value is normally 1A hex, but can be set to anything
by the "/f" option. The "/u" option causes all unallocated
file space to be filled in addition to the file ends.
Discussion:
DOS allocates disk space in terms of fixed-length "chunks" called
clusters. Few files are exactly a multiple of the cluster size in
length, so the unused bytes at the end of the last cluster may
contain sensitive information left in the memory of the system used
to generate or copy the files. PRUNE over-writes the unused bytes
with the DOS end-of-file character, hex 1A, or whatever was specified
if the "/f" option was used. The sizes of the files thus processed
are not affected by this operation. File times and dates are preserved.
Non-printing values can be specified for /f by preceding the decimal
value of each character with a backslash. Thus, an ASCII line feed
can be specified by \010. A fill character having the value of the
backslash can be specified either by two consective backslashes, or
by the sequence \92.
If the "/u" option is specified, all unallocated storage is cleared to
heaxdecimal "F6".
Standard DOS I/O is used, so PRUNE should work on any disk, including
RAMDisk.
Examples:
PRUNE /F "EMPTY SPACE " /S C:\*.* D:\*.*
All files on drives C: and D: are PRUNE-d, the fill pattern used is
"EMPTY SPACE ".
PRUNE /S D:\DUMMY\*.EXE
All .EXE files in the subdirectory "DUMMY" and any of its subdirec-
tories are pruned, using the value 1A hex.
PRUNE /U /S /F \00 \*.*
All files on the current drive are PRUNE-ed with a fill pattern of
nulls. Unallocated file space is filled with hex F6.
Copyright 1989, 1990, 1992 by
Sydex
P.O. Box 5700
Eugene, OR 97405
(503) 683-6033 (voice)
(503) 683-1622 (FAX)
All rights reserved.
NOTICE: This product is supplied "as-is". No warranties of any
kind are given by Sydex, nor will Sydex be held liable for any
damage, either accidental or intentional, resulting from the use
of this or any other program.
Sydex hereby grants license to freely reproduce and redistribute this
program, provided that no fee is charged for the program. A small fee,
not to exceed $10 may be charged to cover the costs of reproduction and
distribution of this program. This program and its documentation may
not be altered or modified in any way.
Any other use or application of PRUNE or its documentation constitutes
a violation of copyright and may be subject to criminal and/or civil
prosecution.