The Fas Model SP 602 is an Italian single-action .22 Long Rifle calibre target-shooting pistol produced since 1986. The Fas Model SP 602 takes a 5-round magazine and features adjustable sights. Research Fas Model SP 602
The Fas Model SP 603 is an Italian single-action .32 Smith and Wesson calibre target-shooting pistol produced since 1986. The Fas Model SP 603 takes a 5-round magazine and features adjustable sights. Research Fas Model SP 603
The SP-19 was a Brazilian single-seat sailplane first flown in 1964. The SP-19 was a high-wing cantilever monoplane of wooden construction with a top speed of 150 kmh in smooth air. Research SP-19
The EXE virus concept is as follows: first, the original Disk Transfer Address is preserved to avoid changing command-line text. Also initial values of the CS, IP, SS, SP DS and ES registers are saved (to be restored on exit from virus code). The virus is to be appended to the original code and, of course, has to be relocated before it's executed. Thus, the virus looks for an EXE file. Then it has to know if this is in fact an EXE (checking for the magic ' MZ' signature) and if there is any free space in the program's relocation table. This is checked by substracting the relocation table end (i.e. sum of table start and number of relocation items, multiplied by the table entry size) from the EXE header size. A smart virus shouldn't infect a file that's already infected. So the first four bytes of code to be executed are compared against the virus code. If they match one another, no infection takes place. Other signature methods are used, but this is the most common. Having found a suitable file, the virus computes
its code end and appends itself at the end of code, writing at an alignment to the last 512-bytes page boundary if necessary. The original start address is preserved inside the virus, and the CS:IP value in the EXE header is changed, so that the virus code is executed first. The number of pages is changed, together with the Last Page Size and Number Of Relocation Items. A new relocation item address is appended to the relocation table, pointing to the segment of the far jump in the virus (this is the jump the virus uses to return to the original code). Upon returning from the virus, all the saved registers and DTA are restored to reestablish the environment state as if no virus existed. The real trouble with EXEs is that DOS pays a little (if any) attention to the Last Page Size. Therefore EXE files ofen have this zeroed, even if they have some code on the last page. Writing to the last page can cause a system crash while an infected file is being executed. To solve the problem, one should first test if the EXE file really ends as the header
contents say and move to the last page end instead of appending any bytes, if possible. Another problem is infecting EXEs containg debug info. Debug info comes in various formats, and often contains vital information placed behind the actual code. This info gets destroyed when the file becomes infected, sometimes causing the infected program to crash. Research Exe Virus Concept
SP is an abbreviation for Shore Patrol
SP is an abbreviation for Short Play
SP is an abbreviation for Southern Pacific
SP is an abbreviation for StackPointer
SP is an abbreviation for Star Patrol
SP is an abbreviation for Species
SP is an abbreviation for Self Propelled
SP is an abbreviation for Shore Police
SP is an abbreviation for Signal Processor
SP is an abbreviation for Sine Prole
SP is an abbreviation for Single Pole
SP is an abbreviation for Special Performance
SP is an abbreviation for Specialist
SP is an abbreviation for Spurious PM
SP is an abbreviation for Stellar Polarimeter Research SP
The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
Abbreviations
Research Fas Model SP 602
