Hello, I know how to write simple tsr programs in (16-bit) assembly language in dos. But I would like to know whether windows have tsr programs, if so, do the technique to write is also similiar (such as intercepting interrupts). And can the programs in system trays be call tsr according tsr concepts. And how to write a progam to stay in the memory while others are running (like the one at the bottom right conor on the screen)? Would anybody please to help me ? because i really desire to know. My tsr program in dos cannot work in windows anymore. Thanks a lot!

I think what you want is called a 'system service'. They can be started at boot, and remain until the system crashes or is shutdown. I know nothing about the API, but this should be documented in any decent Windows C/C++ compiler docs. Can you write them in Assembler? I would guess you can, but I'd prototype in C first. Guy

I used to teach myself Pascal and Assembly, but now i have to learn C. Ah, I like to ask another question. In DOS, we have int 21h to call the DOS functions, but it won't work in windows (I guess), however, will the interrupts of BIOS with different functions still work well in woindows? Thanks! HSon

Hello, TSR has been replaced with threads which are different in a lot of ways, time slice and priority levels, interrupts no longer used. In windows you do not have to call for interupts as in dos, you the memory and time slice is allocated by the system when your application starts and is recovered when you exits or part of your application go's out of scope. There are many langages that you can use for Windows, the most popular are C++(powerful) and Visual Basic(easy).

PS: Windows applications do not have to be visible to be running, With (SERVICES) the user does'nt need to be Logged In for the application to be running in the background, some application are simply invisible which is bool, others just don't have a user interface and others that are(.dll) "dynaiclly linking library", which exposes there methods or API only to other applications. The tray on the bottom is just part of Windows API as stated above by Guy, "ComponentTray class".

hi fred, do u mean to say that u don't use interrupts any more in windows...... well i had made some screen saver programs in C as a tsr by capturing the timer interrupt, and when i execute it in the command prompt of windows 98 its runs as long as the command prompt is there or Turbo C++ IDE is running or any DOS based platform is running..... this means u still have interrupts there in win 9x..... i'd wait for a comment....

Yes they may run in the DOS or CMD window, which itself is a window/ one thread that is handled by Win16 (16-bit MS-DOS emulation layer) which simulates the native Windows 3.x processing. DOS emulation layer ------------------- Dosx.exe = DPMI interface TSR program Himem.sys = Extended memory specification (XMS) driver Mscdexnt.exe = MSCDEX interface TSR program Ntdos.sys = MS-DOS system kernel Ntio.sys = MS-DOS input/output (I/O) kernel Redir.exe = NetBIOS interface TSR program Windows 3.1 kernel layer -------------------------- Toolhelp.dll = Win16 tool helper API User.exe = Win16 User Manager interface Gdi.exe = Win16 Graphics Manager interface Shell.dll = Win16 shell interface Krnl386.exe = Win16 kernel Mmsystem.dll = Win16 multimedia API