Text Processing (Grep/Sed/Awk)

Stop regex from making your brain melt when you need to match across lines

🧩 The Challenge

You’ve got a giant multi-line configuration block and all you want is to pull the stuff between two markers, but standard grep just wants to look line-by-line. I spent way too long trying to cobble together complex pipe chains before I finally learned how to handle this properly.

💡 The Fix

Use awk with a custom record separator to treat the whole block as one piece of data, which lets you grab everything inside the brackets without losing your mind. It makes parsing things like indented JSON or weird legacy config files actually readable.

awk -v RS='\\{\\}' '/start_marker/,/end_marker/' config.file

⚙️ Why It Works

By setting the record separator to an empty string or a custom pattern, awk stops caring about newlines and treats the file as a collection of chunks. It’s way cleaner than trying to shove everything into a one-liner with nested sed commands.

🚀 Pro-Tip: If your markers contain special regex characters, make sure you escape them or just use string comparisons instead of pattern matching.

Linux Tips & Tricks | © ngelinux.com | 7/26/2026