dos
How to create empty text file from a batch file?
copy NUL EmptyFile.txt DOS has a few special files (devices, actually) that exist in every directory, NUL being the equivalent of UNIX’s /dev/null: it’s a magic file that’s always empty and throws away anything you write to it. Here’s a list of some others; CON is occasionally useful as well. To avoid having any output … Read more
How buffered input works
Looking at how you defined your input buffer (buf: db 20 dup (‘$’)), I get it that you want to cut corners and have the input already $-terminated ready for re-displaying it. Sadly this messes up the required settings for the DOS input function 0Ah and your program is in serious problems with a potential … Read more
Displaying numbers with DOS
It’s true that DOS doesn’t offer us a function to output a number directly. You’ll have to first convert the number yourself and then have DOS display it using one of the text output functions. Displaying the unsigned 16-bit number held in AX When tackling the problem of converting a number, it helps to see … Read more
What needs to be added
Jacob, run help on a cmd prompt and you will get a huge list of available commands for you to implement C:\>help For more information on a specific command, type HELP command-name ASSOC Displays or modifies file extension associations. ATTRIB Displays or changes file attributes. BREAK Sets or clears extended CTRL+C checking. BCDEDIT Sets properties … Read more