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Ada (computer Virus)
Ada is a computer virus that can affect any of the DOS operating systems. Ada was first discovered in 1991. History Ada virus was first discovered in Argentina in . Characteristics Ada is a memory resident virus that infects files. The Ada virus mainly targets .COM files, specifically COMMAND.COM and stays in the memory of the computer it infects after the program it infected executes. Infected programs have 2,600 bytes additional data inserted at the beginning of the file, and the file itself contains the text strings: * COMMAND.COM * PCCILLIN.COM * PCCILLIN.IMG * HATI-HATI !! ADA VIRUS DISINI !!Delete Another version of Ada has these text strings along with the strings BASURA BASURA repeated numerous times. Computers infected with the Ada virus often have a slow clicking sound emitting from their speakers; this clicking may sometimes change in pitch. Infected computers may show a "Disk Full" error even if the disk still has space on it. While infected with the Ada virus, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Virus
A computer virus is a type of computer program that, when executed, replicates itself by modifying other computer programs and inserting its own code. If this replication succeeds, the affected areas are then said to be "infected" with a computer virus, a metaphor derived from biological viruses. Computer viruses generally require a host program. The virus writes its own code into the host program. When the program runs, the written virus program is executed first, causing infection and damage. A computer worm does not need a host program, as it is an independent program or code chunk. Therefore, it is not restricted by the host program, but can run independently and actively carry out attacks. Virus writers use social engineering deceptions and exploit detailed knowledge of security vulnerabilities to initially infect systems and to spread the virus. Viruses use complex anti-detection/stealth strategies to evade antivirus software. Motives for creating viruses can inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COM File
A COM file is a type of simple executable file. On the Digital Equipment Corporation (DEC) VAX operating systems of the 1970s, .COM was used as a filename extension for text files containing commands to be issued to the operating system (similar to a batch file). With the introduction of Digital Research's CP/M (a microcomputer operating system), the type of files commonly associated with COM extension changed to that of executable files. This convention was later carried over to DOS. Even when complemented by the more general .exe, EXE file format for executables, the compact COM files remained viable and frequently used under DOS. The .COM file name extension has no relation to the .com (for "commercial") top-level Internet domain name. However, this similarity in name has been exploited by malware writers. DOS binary format The COM format is the original binary executable format used in CP/M (including SCP (operating system), SCP and MSX-DOS) as well as DOS. It is very sim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, the fourth-largest country in the Americas, and the eighth-largest country in the world. It shares the bulk of the Southern Cone with Chile to the west, and is also bordered by Bolivia and Paraguay to the north, Brazil to the northeast, Uruguay and the South Atlantic Ocean to the east, and the Drake Passage to the south. Argentina is a federal state subdivided into twenty-three provinces, and one autonomous city, which is the federal capital and largest city of the nation, Buenos Aires. The provinces and the capital have their own constitutions, but exist under a federal system. Argentina claims sovereignty over the Falkland Islands, South Georgia and the South Sandwich Islands, and a part of Antarctica. The earliest recorded human prese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Virus
A computer virus is a type of computer program that, when executed, replicates itself by modifying other computer programs and inserting its own code. If this replication succeeds, the affected areas are then said to be "infected" with a computer virus, a metaphor derived from biological viruses. Computer viruses generally require a host program. The virus writes its own code into the host program. When the program runs, the written virus program is executed first, causing infection and damage. A computer worm does not need a host program, as it is an independent program or code chunk. Therefore, it is not restricted by the host program, but can run independently and actively carry out attacks. Virus writers use social engineering deceptions and exploit detailed knowledge of security vulnerabilities to initially infect systems and to spread the virus. Viruses use complex anti-detection/stealth strategies to evade antivirus software. Motives for creating viruses can inclu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Memory Resident
A terminate-and-stay-resident program (commonly TSR) is a computer program running under DOS that uses a system call to return control to DOS as though it has finished, but remains in computer memory so it can be reactivated later. This technique partially overcame DOS's limitation of executing only one program, or task, at a time. TSRs are used only in DOS, not in Windows. Some TSRs are utility software that a computer user might call up several times a day, while working in another program, using a hotkey. Borland Sidekick was an early and popular example of this type. Others serve as device drivers for hardware that the operating system does not directly support. Use Normally DOS can run only one program at a time. When a program finishes, it returns control to DOS using the system call . The memory and system resources used are then marked as unused. This makes it impossible to restart parts of the program without having to reload it all. However, if a program ends with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHKDSK
In computing, CHKDSK (short for "check disk") is a system tool and command in DOS, Digital Research FlexOS, IBM/Toshiba 4690 OS, IBM OS/2, Microsoft Windows and related operating systems. It verifies the file system integrity of a volume and attempts to fix logical file system errors. It is similar to the fsck command in Unix and similar to Microsoft ScanDisk, which co-existed with CHKDSK in Windows 9x and MS-DOS 6.x. Implementations An early implementation of a 'CheckDisk' was the ''CHECKDSK'' that was a part of Digital Equipment Corporation hardware's diagnostics, running on early 1970s TENEX and TOPS-20. SCP 86-DOS The CHKDSK command was first implemented in 1980 by Tim Paterson and included in Seattle Computer Products 86-DOS. MS-DOS / IBM PC DOS The command is available in MS-DOS versions 1 and later. CHKDSK is implemented as an external command. MS-DOS versions 2.x - 4.x use chkdsk.com as the executable file. MS-DOS versions 5.x and later use chkdsk.exe as the exec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
