Randwp is a simple tool for selecting a random JPEG wallpaper from a folder and writing it in BMP format to a destination path. It is an extended DOS executable, and can be used in DOS or anything compatible. Usage is quite simple:
Usage: randwp searchpath outname
Where:
searchpath : The path to search for JPEG images
outname : The output path and filename to write the .BMP image
To integrate in a DOS or Win 9x system, the easiest option is to simply add this tool to the autoexec.bat file. As such, it will pick a new wallpaper each time the machine is started. For example, the line in my Retro PC's autoexec.bat is:
C:\APPS\RANDWP.EXE D:\FILES\PICTURES C:\WINDOWS\RANDOM.BMP
As implied above, this tool is rather limited and only works with JPEG source files and BMP output files. Internally, it is based on version 6b of libjpeg by the Independent JPEG Group. The application is built with OpenWatcom.