... routine moves the virus (this program) to the end of the COM file;Basically, it just copies everything here to there, and then goes and;adjusts the 5 bytes at the start of the program and the five ... ss:[bp+20],ax139 The Little Black Book of Computer VirusesVIRUS_START: call GET_START ;get start address;This is a trick to determine the location of the start of the program. We put ;the address of GET_START ... > 1. If the disk is infected,;then instead of reading the true data there, return a block of 0’s, since;0 is the data stored in a freshly formatted but unused sector. This will;fake the caller...