The simple idea is simple: periodically automatically generate file locally and upload it to web server using ftp.
Several years ago when I was passionate about Sudoku game I created my own Sudoku generator which is located in http://sudoku.smike.ru. There were several version of the generator. The version presented here generates Sudoku in PDF format and uploads it to web server. The code is C++ Windows console application, no third party libraries were used for PDF maker, it was written by me, not perfect but works. The source code may be downloaded from here.
There are three steps of execution:
1. Random Sudoku generation
2. Saving Sudoku as sdk.pdf file
3. Upload sdk.pdf file to the web server (ftp server, remote file directory, credentials are taken from sdkconsole10.dat file, which should be located in the same directory as sdkconsole10.exe.
After adding the windows task scheduler the sdk.pdf is updated recursively.
How sdkconsole10.exe looks in the task scheduler.