Vim & Sed: Efficient Text Editing and Search-Replace

Advanced Vim Search and Replace

Finding and replacing text efficiently within a file is a key skill for managing configuration files.

• /search_term: Search forward for a specific string. Press n to go to the next occurrence or N for the previous.
• :s/old/new/: Replace the first occurrence of “old” with “new” in the current line.
• :s/old/new/g: Replace all occurrences (globally) of “old” with “new” on the current line.
• :%s/old/new/g: Search and replace every occurrence of “old” with “new” in the entire file.
• :g/pattern/d: Search the entire file and delete all lines that match the specified pattern.

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Opening Files at Specific Locations

Instead of just opening a file and scrolling, use these flags to jump directly to your target.

• vim +$ ~/hosts: Open the file and jump directly to the last line.
• vim +8 ~/hosts: Open the file and jump to
• vim +/linux/ ~/hosts: Open the file and jump to the first occurrence of the word “linux”.
• vimtutor: Launch the built-in tutorial to practice Vim basics directly in the terminal.

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Stream Editing with sed

For quick, non-interactive changes, sed allows you to modify files without opening them.

• sed -i 's/google/cloudflare/' ~/hosts: Find the first occurrence of “google” and replace it with “cloudflare” directly in the file.
• sed -i '$d' ~/hosts: Delete the last line of the file.
• sed -i '1i "This is a test file"' ~/hosts: Insert a new line at the very top (Line 1) of the file.

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Vim Shortcuts

Navigation

• gg: Jump to the very first line of the file.
• G: Jump to the very last line of the file.
• :<number>: Jump to a specific line (e.g., :48).
• H: Move cursor to the High (top) of the current screen.
• L: Move cursor to the Low (bottom) of the current screen.
• %: Jump between matching brackets (), [], or {}.

Editing & Deletion

• i: Enter Insert mode at the cursor position.
• o: Open a new line below the current one and enter Insert mode.
• O: Open a new line above the current one and enter Insert mode.
• dd: Delete (cut) the current line.
• yy: Yank (copy) the current line.
• p: Put (paste) the yanked or deleted text after the cursor.
• u: Undo the last action.
• .: Repeat the last editing command (the “Dot” command).

Power Moves

• ci": Change Inside double quotes (clears text and enters Insert mode)
• di{: Delete Inside curly braces (perfect for cleaning out code blocks).
• ctrl + v: Enter Visual Block mode to select vertical columns of text.
• :%s/old/new/g: Search and replace “old” with “new” globally in the file.

Saving and Exiting Shortcuts

• :w: Write (save) the changes to the file.
• :q: Quit (fails if there are unsaved changes).
• :wq!: Force write (save) and quit, even for files with restricted permissions.
• :x: Save and exit (only writes to disk if changes were actually made).
• :q!: Quit immediately without saving any changes.

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