Cheatsheet for GNU Basic and Extended Regular Expressions and differences between grep, sed and awk.
  • acockworkorange
    4·
    6 hours ago
    • sed requires both ( and )characters to be escaped (in ERE mode), whereas grep and awkdon’t require ) to be escaped.
    • sed requires { to be escaped (in ERE mode) even if it isn’t part of a valid quantifier syntax, whereas grep and awk don’t require escaping. For example, you’d need \{a} in sed whereas {a} is enough for the other two.
    • In BRE mode, grep and sed don’t require ^ and $ to be escaped if they are used away from their customary positions.

    Fuck that.

    Edit: I’m not complaining about the the page, it looks nice and polished. It’s the inconsistencies among the GNU tools in handling regex that grind me.

    • Badabinski@kbin.earth
      4·
      5 hours ago

      Yeah, every now and then I take a step back and say “what the fuck did they build?” when dealing with some of the GNU tools. Twenty minutes later I’ll start complaining about how the BSD version of something from coreutils lacks a GNU argument that would make my life about 83% easier.

      It’s like a sick sort of Stockholm Syndrome. I do genuinely like GNU coreutils, but there’s some baffling shit present.