Rapidly performs a File|Save for all open files in all open projects.
For untitled files, File|Save As is invoked. If you have multiple untitled files then you will get a Save As dialog for each of them. If you cancel the Save As dialog then you cancel saving that file and any other files for which you were not prompted yet. This does not undo saving files for which you already clicked Save on the Save As dialog.
If you have a mixture of untitled files and previously saved files with unsaved changes then EditPad Pro first prompts to save each untitled file. When all untitled files are saved it automatically saves all previously saved files. So if you click Cancel on the Save As dialog for the first untitled file then no files are saved at all.
Project|Save All Files in Project