$ curl cheat.sh/
# egrep
# Find patterns in files using extended regular expression (supports `?`, `+`, `{}`, `()` and `|`).
# More information: <https://manned.org/egrep>.

# Search for a pattern within a file:
egrep "search_pattern" path/to/file

# Search for a pattern within multiple files:
egrep "search_pattern" path/to/file1 path/to/file2 path/to/file3

# Search `stdin` for a pattern:
cat path/to/file | egrep search_pattern

# Print file name and line number for each match:
egrep --with-filename --line-number "search_pattern" path/to/file

# Search for a pattern in all files recursively in a directory, ignoring binary files:
egrep --recursive --binary-files=without-match "search_pattern" path/to/directory

# Search for lines that do not match a pattern:
egrep --invert-match "search_pattern" path/to/file

$
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