I'd like to make a batch file that, at runtime, increments a counter set as an environment variable, and saves it in a file. How can I do this? I'm using DOS 6.22. All the OSes I use: Windows XP, Windows 98, MS-DOS 6.22, OpenBSD 2.6, DLX Linux. I have 4 computers, one of which is emulated.

AFAIK 6.22 has no provision for incrementing per se. You might try something in debug. But it gets messy. ===================================== If at first you don't succeed, you're about average. M2

You could do something silly like this but it only goes from 0 to 9 and then back to 0 again. Before you start echo set snake=0 > snake.bat The script call setsnake goto SS%snake% :ss0 set snake=1 goto ssend :ss1 set snake=2 goto ssend :ss2 set snake=3 goto ssend :ss3 set snake=4 goto ssend :ss4 set snake=5 goto ssend :ss5 set snake=6 goto ssend :ss6 set snake=7 goto ssend :ss7 set snake=8 goto ssend :ss8 set snake=9 goto ssend :ss9 set snake=0 :ssend echo set snake=%snake% > setsnake.bat snake.bat will contain the string that sets snake to the next number.

Cup, I like your idea. I think I'll try it on my XP box. Thanks!

On NT/2K/XP, you have set /a for doing arithmetic. set /a doesn't exist on 6.22.

On NT-based systems I use SET /A and /P a lot. All the OSes I use: Windows XP, Windows 98, MS-DOS 6.22, OpenBSD 2.6, DLX Linux. I have 4 computers, one of which is emulated.

If you use 4DOS, you can do something like this (... means other commands you want to execute): SET var=0 ... SET var=%@inc[%var] ... ECHO SET var=%var > SETVAR.BAT