Terminate and stay resident program. In computers, a terminate and stay resident program (commonly referred to by the initialism. TSR) is a computer program that uses a system call in DOSoperating systems to return control of the computer to the operating system, as though the program has quit, but stays resident in computer memory so it can be reactivated by a hardware or software interrupt. TSR is unique to DOS and not used in Windows. Some terminate and stay resident programs were utility programs 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. Other TSRs serve as device drivers for hardware that the operating system did not directly support. Using TSRs. To stop running, it gives control back to the DOS shell program, COMMAND. COM, using the system call. INT 2. 1h/4. Ch. This in effect makes it impossible to restart parts of it again without reloading it from scratch. However, if a program ends with the system call INT 2. INT 2. 1h/3. 1h, the operating system does not reuse a certain specified part of the program's memory. The original call, INT 2. Using this call, a program can make up to 6. KB of its memory resident.
Chapter 5160-3 Long-Term Care Facilities; Nursing Facilities; Intermediate Care Facilities for the Mentally Retarded. 5160-3-01 Definitions. Except as otherwise provided in Chapter 5101:3-3 of the Administrative Code.MS- DOS version 2. INT 2. 1h/function 3. Keep Process'), which removed this limitation and let the program return an exit code. Before making this call, the program can install one or several interrupt handlers pointing into itself, so that it can be called again. Installing a hardware interrupt vector allows such a program to react to hardware events. Windows startup programs - Database search. If you're frustrated with the time it takes your Windows 8/7/Vista/XP PC to boot and then it seems to be running slowly you may have too many programs running at start-up - and you. You are here: Help > Operating System > Microsoft Windows Help. How to remove TSRs and startup programs. This document contains steps on removing Terminate-and-Stay-Resident programs temporarily from memory and how to prevent. This chapter was adapted from the Department of State Post Report 2000 for Bahrain. Supplemental material has been added to increase coverage of minor cities, facts. System software is an essential part of a computer system. This chapter defines system software and discusses two types of system software: operating systems and utility programs. You learn what an operating system is and. Computer jargon explained. Compiled by Jon Storm. You will certainly have noticed that there is lots and lots of strange gibberish associated with computers; and the industry just loves acronyms. Remove SearchNet from Windows 7 / Vista / XP systems. Remove SearchNet from Windows 10 / Windows 8 systems. Installing a software interrupt vector allows it to be called by the currently running program. Installing a timer interrupt handler allows a TSR to run periodically (see ISA and programmable interval timer, especially the section . The stored address is called before or after the TSR has received the interrupt and has finished its processing, in effect forming a singly linked list of interrupt handlers, also called interrupt service routines, or ISRs. This procedure of installing ISRs is called chaining or hooking an interrupt or an interrupt vector. By chaining the interrupt vectors TSR programs could take complete control of the computer. A TSR could have one of two behaviors: Take complete control of an interrupt by not calling other TSRs that had previously altered the same interrupt vector. Cascade with other TSRs by calling the old interrupt vector. This could be done before or after they executed their actual code. This way TSRs could form a chain of programs where each one calls the next one. The . Viruses would react to disk I/O or execution events by infecting executable (. EXE or . COM) files when they were run and data files when they were opened. Parts of DOS itself, especially in DOS versions 5. DOSKEY command- line editor and various other installable utilities which were installed by running them at the command line (manually, from AUTOEXEC. BAT or through INSTALL from within CONFIG. SYS) rather than loading them as device drivers through DEVICE statements in CONFIG. SYS. A TSR program can be loaded at any time; sometimes, they are loaded immediately after the operating system's boot, by being explicitly loaded in the AUTOEXEC. BAT batch program, or alternatively at the user's request (for example, Borland's Sidekick and Turbo Debugger, Quicken's Quick. Pay, or Fun. Stuff Software's Personal Calendar). These programs will, as . Some of them do not have an option for unloading themselves from memory, so calling TSR means the program will remain in memory until a reboot. However unloading is possible externally, using utilities like the MARK. EXE/RELEASE. EXE combo by Turbo. Power Software or soft reboot TSRs which will catch a specific key combination and release all TSRs loaded after them. As the chain of ISRs is singly linked, there is no provision for discovering the previous handler's address (other than attempting to trace back the interrupt chain), or to inform its predecessor that it needs to update its . This gave rise to TSR cooperation frameworks such as Tes. Se. Ract and AMIS. AMIS provides ways to share software interrupts in a controlled manner. It is modeled after IBM's Interrupt Sharing Protocol, originally invented for sharing hardware interrupts of an x. AMIS services are available via Int 2. Dh. It existed alongside several other competing specifications of varying sophistication. Many of the programs effectively hijacked the operating system in varying documented or undocumented ways, often causing systems to crash on their activation or deactivation when used with particular application programs or other TSRs. As explained above, some viruses were coded as TSRs, and were deliberately troublesome. Additionally, all program code in DOS systems, even those with large amounts of physical RAM, had to be loaded into the first 6. KB of RAM (the conventional memory). TSRs were no exception, and took chunks from that 6. KB that were thus unavailable to application programs. This meant that writing a TSR was a challenge of achieving the smallest possible size for it, and checking it for compatibility with a lot of software products from different vendors. Many gamers had several boot disks with different configurations for different games. In later versions of MS- DOS, . In the mid- to later 1. DOS, the 6. 40 KB limit was eventually overcome by putting parts of the game's data and/or program code above the first 1 MB of memory and using the code below 6. KB to access the extended memory (using DOS extension methods), with code being swapped into the lowest 1 MB of RAM as overlays. Because programming with many overlays is a challenge in and of itself, once the program was too big to fit entirely into about 5. KB, use of extended memory was almost always done using a third- party DOS extender implementing VCPI or DPMI, because it becomes much easier and faster to access memory above the 1 MB boundary, and possible to run code in that area, when the x. However, since DOS and most DOS programs run in real mode (VCPI or DPMI makes a protected mode program look like a real mode program to DOS and the rest of the system by switching back and forth between the two modes), DOS TSRs and device drivers also run in real mode, and so any time one gets control, the DOS extender has to switch back to real mode until it relinquishes control, incurring a time penalty (unless they utilize techniques such as DPMS or CLOAKING). With the arrival of expanded memory boards and especially of Intel 8. KB to load TSRs. This required complex software solutions, named expanded memory managers. Some memory managers are QRAM and QEMM by Quarterdeck, 3. MAX by Qualitas, CEMM by Compaq and later EMM3. Microsoft. The memory areas usable for loading TSRs above 6. KB are called . Later, memory managers started including programs which would try to automatically determine how to best allocate TSRs between low and high memory (Quarterdeck's Optimize or Microsoft's Mem. Maker) in order to try to maximize the available space in the first 6. KB. Decline. TSRs have now almost disappeared, as multitasking operating systems such as Windows Vista, Windows 7, Mac OS X, and Linux provide the facilities for multiple programs and device drivers to run simultaneously without the need for special programming tricks, and the modern notion of protected memory makes the kernel and its modules exclusively responsible for modifying an interrupt table.
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