Adding line feeds into a form field is one way crackers attempt to break into your script to apply their own mods. By testing for it and stripping them out of form fields where such characters are not valid input you can block that method of cracking your script.
I have been programming computers since the late 1970s, performing a wide variety of different computer programming jobs, and using a large range of different languages - mostly writing accounting and financial systems for mainframe computers. Since the market for mainframe computer skills moved offshore I have been writing about computers, teaching computer courses in the classroom, and also doing accounting work.
Computer help on a range of different computer related topics
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