Off the top of my bookmarks, I would suggest these: • https://www.gnu.org/prep/standards/standards.html#Command_002dLine-Interfaces https://www.gnu.org/prep/st

Off the top of my bookmarks, I would suggest these: • https://www.gnu.org/prep/standards/standards.html#Command_002dLine-Interfaces https://www.gnu.org/prep/standards/standards.html#Command_00... • http://www.catb.org/~esr/writings/taoup/html/ http://www.catb.org/~esr/writings/taoup/html/ • https://www.cons.org/cracauer/sigint.html https://www.cons.org/cracauer/sigint.html