Ripgrep

Ripgrep is a line-oriented search tool that recursively searches directories for regex patterns¹. It’s designed for speed and respects .gitignore rules when searching within git repositories.

Case Sensitivity

Ripgrep supports three case sensitivity modes:

Smart Case (--smart-case) is case-insensitive unless the pattern contains uppercase letters. Pattern hello matches “hello”, “Hello”, “HELLO” while pattern Hello only matches “Hello”.

Case Insensitive (--ignore-case or -i) is always case-insensitive regardless of pattern. Pattern Hello matches “hello”, “Hello”, “HELLO”.

Case Sensitive (--case-sensitive or -s) is always case-sensitive. Pattern hello only matches “hello”.

Core Flags

JSON Output (--json) outputs results in JSON format with structured data for programmatic parsing. Each line is a JSON object representing different message types.

rg --json "pattern" files...

Respect Gitignore (--no-require-git) makes ripgrep respect .gitignore rules even when searching outside of a git repository.

rg --no-require-git "pattern" files...

Pattern Types

Regex mode is the default². Standard regex patterns work out of the box:

rg "TODO|FIXME" notes/

Fixed Strings mode (--fixed-strings or -F) treats the pattern as a literal string rather than regex. Useful when searching for special characters that would otherwise need escaping:

rg -F "function()" notes/

PCRE2 Engine (--pcre2) uses PCRE2 for advanced regex features like lookbehind, lookahead, and backreferences³:

rg --pcre2 "(?<=TODO: )\w+" notes/

Context Lines

Shows N lines before and after each match:

rg -C 3 "pattern" notes/

Available options:

• -A N: N lines after the match
• -B N: N lines before the match
• -C N: N lines before and after the match

JSON Output Format

When using --json, ripgrep outputs newline-delimited JSON messages.

Message types include:

begin - Start of results for a file:

{
  "type": "begin",
  "data": {
    "path": {"text": "/path/to/note.md"}
  }
}

match - A search match:

{
  "type": "match",
  "data": {
    "path": {"text": "/path/to/note.md"},
    "lines": {"text": "This line contains the match\n"},
    "line_number": 42,
    "submatches": [{"start": 15, "end": 20}]
  }
}

context - Context lines (when using -C, -A, or -B):

{
  "type": "context",
  "data": {
    "path": {"text": "/path/to/note.md"},
    "lines": {"text": "context line before match\n"},
    "line_number": 41
  }
}

end - End of results for a file:

{
  "type": "end",
  "data": {
    "path": {"text": "/path/to/note.md"}
  }
}

summary - Final statistics:

{
  "type": "summary",
  "data": {
    "elapsed_total": {"secs": 0, "nanos": 123456},
    "stats": {
      "matched_lines": 5,
      "matches": 7
    }
  }
}

Exit Codes

Ripgrep uses exit codes to indicate search status:

• 0: Matches found (success)
• 1: No matches found (not an error)
• 2+: Error occurred (file not found, permission denied, etc.)

When using ripgrep programmatically, exit code 1 should be treated as success (just no results).

Performance

Operating systems impose limits on command-line argument length. When searching thousands of files, split them into batches. A chunk size of 1000 files per invocation is a safe default.

Process JSON output line-by-line rather than reading all results into memory:

rg --json "pattern" notes/ | while IFS= read -r line; do
  echo "$line" | jq '.type'
done