You use piping and redirecting as an alternative in case the DOS tool you use doesn't support the proper parameters (like paths in filenames, etc).
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The reason why you get a "page not found" is not because of a damaged file or faulty download, but because your Windows is propbably not up to date or is set to block certain file content.
Also make sure you first download the file and then open it (so don't open it directly from the download dialog in MSIE as it will block the contents by default when the file is opened directly from the download).
see here:
http://geekswithblogs.net/evjen/archive/2006/06/29/83567.aspx
or here:
http://www.helpscribble.com/chmnetwork.html
Everything is also recapped here:
Silentdragon's reply to Official Scripting Documentation doesn't work.
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In regards to timers, see the
Plus! Scripting documentation. Timers are event driven, you don't need any loop at all.
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PS, quickly looking at
http://docs.miktex.org/manual/texfeatures.html#includedirectory
I see there is a command line parameter "-include-directory=dir".
Then there is also an output directory parameter:
http://docs.miktex.org/manual/texfeatures.html#outputdirectory
etc...
So there sure are a lot more possebilities and at first sight it looks like you can do everything from one command line using only the LATEX command and the proper parameters to create the DVI file.
And by very quickly skimming over the docs I found there are also some commands you can use inside a tex file to run other latex related things, so it might even be possible to also integrate the convertion to PNG in that same TEX file, dunno.
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So, everything boils down to reading the documentations of the stuff you wanna use. This means the docs for MikTeX, The
Plus! Scripting Docs, and the
Windows Script Docs.