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When the batch file finishes, is removed from memory and control returns to the text editor. All rights reserved.Ģ 2 /C make16.bat AddSub (called the command processor) executes the batch file, passing it the name "AddSub". A typical command line is as follows: Copyright 2002 Kip R.
Irvue command line how to#
We show on this Web site how to customize the Tools menu of TextPad and Visual Studio to assemble and link MASM programs. They do this by loading a second copy of the Command processor ( or cmd.exe) and passing it arguments on the command line. Many programs indirectly execute MS-DOS commands.
Irvue command line code#
The return code can be retrieved by calling INT 21h Function 4Dh. When it exits, the child program can optionally return an integer return code between It does this by passing the integer in AL when it calls INT 21h Function 4Ch to terminate. The block is an array of null-terminated strings containing system variables such as PATH, PROMPT, and COMPSEC. You can also create a new environment block for the child program., up to 32K in size, and store parameters in the block.
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You can pass a string on the child program s command line, as if the string were typed at the MS-DOS prompt. Parameter passing is a little awkward, but easily possible. The parameter block is passed to the child program when INT 21h is called.
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Second, the parent program must construct a structure called a parameter block that contains pointers to its own MS-DOS environment, a command-line string, and other miscellaneous information. The allocation is far more generous than necessary, because MS-DOS doesn t know how much memory you plan to use during the program s execution. First, the calling program, which we will call the parent from now on, must resize the default memory allocation assigned to it by MS-DOS when it was loaded. The calling program is suspended, the called program executes, and when it finishes, control returns to the calling program. MS-DOS provides a convenient hook that lets you launch any executable program much in the manner of a subroutine call. The answer to this problem, of course, would be to run a calendar program directly from the text editor. The text editor s author could include code to display calendars, but it would increase the size of the program and probably be a poor imitation of existing calendar programs. You wouldn t want to have to close the editor to view a calendar, of course, but under MS-DOS, you could not run both programs at the same time. Suppose you were using a text editor, and you needed to view a calendar. Many applications rely on other programs to perform useful services. From the start, it was designed to be a simple, single-tasking operating system. Last update: MS-DOS has always taken a fairly straightforward approach to loading and executing programs. 1 Loading and Executing a Child Process by Kip Irvine.