User Guide

AntiViral Toolkit Pro
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code in computer memory after it terminates. This code is typically installed as
an interrupt handler and is executed when an interrupt occurs.
Sector
The smallest physical unit of storage on disk. A disk is divided into sectors when
it is formatted. Each sector can be uniquely addressed. A sector may have both a
physical (relative to the start of the disk, accessed using BIOS calls) and a logical
(relative to the start of a partition, accessed using DOS calls) address. The sector
size is usually 512 bytes.
Stealth
Stealth viruses (invisible viruses) are viruses that intercept DOS calls so that
when an infected file or sector is accessed, the evidence of infection can be
hidden from the calling program. Stealth viruses may employ other techniques
too in order to defeat resident anti-virus monitors. Examples of stealth viruses
are "V-4096", "Fish#6" and "Brain".
Interrupt Vectors Table
A table in memory containing the addresses of interrupt handler routines. It is
placed in the lowest memory addresses (0000:0000 - 0000:03FF) and contains
256 addresses (interrupt vectors) of 4 bytes each.
Relocation Table
see: EXE file
Trojan Horse
A program or routine that performs destructive actions but which masquerades as
something useful.
File
The logical unit of data storage on disk. A files may contain data of any type:
programs, databases, text, etc. A file has attributes such as the file name, file size
(the number of bytes of data it contains) and date and time of last modification.
Physical Sector
see: Sector
Backup
Copies of software and data made on a backup medium such as tape or
removable disk, taken as a precaution against loss of the software or data on the