as same as position of windows,size,open file,etc.
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97answers:
2emacs 23 has the 'desktop.el' package included. You can turn it on with:
M-x customize-variable
desktop-save-mode
This should show you the following screen (or something like it):
Turn on Desktop Save Mode, and save the changes for current and future. Emacs should then save the desktop state each time you exit, and reload that same state on restart.
Many seasoned Emacs users just never shut Emacs down. Suspend, hibernate or leave on the computer. Use emacs-server for persistence. In general Emacs handles long uptimes very well. This is not an option for everyone of course.
Desktop.el is good for reloading all your files, but (unless I'm wrong) I don't think it re-loads your window configuration.
Policy Switch at least allows you to save window configurations manually and cycle through them, though it doesn't do automatic saving and restoration. So it doesn't scratch the itch you asked for, but it may meet the same need a different way.