grep

grep is a command for searching plain text data sets for lines that match a regular expression.

~/.bash_profile

alias grep='grep --color=auto'

Common options

-o, --only-matching

-a, --text equivalent to --binary-files=text

-i

-I Ignore binaries

-r

-v

-w

--exclude

--exclude-dir

grep -r --color=always -n -H --exclude-dir='.*'

--line-buffered

 -H, --with-filename

Examples

• grep -ir "YOUR TEXT" *

Search for a pattern: TEXT="OTHER_TEXT"

• grep -o 'TEXT="\w*"' index.html

Search for a pattern: TEXT="OTHER _TE XT" including spaces:

• grep -o 'TEXT="[ a-zA-Z0-9_]*"' index.html

Search in hidden folders:

• grep -ir your-search * .[^.]*

End of line:

• grep your-search$

Add line:

• grep -qxF 'your text "additional text"' yourfile.txt || echo 'your text "additional text"' >> yourfile.txt

• grep .
• grep -I (Ignore binary files)
• grep -c
• grep -r. Related commands: PAN-OS: show log system direction equal backward
• grep -w
• grep -A
• grep -B
• grep -q, quiet
• grep -F, pattern is a plain string
• grep -x match the whole line

Related

• findstr (Windows)
• ggrep macOS
• stdin, stdout, stderr, 2>&1
• include (Cisco IOS)
• awk '/TEXT_TO_SEARCH/{f=1}f' file
• ag
• git grep "your_string" $(git rev-list --all)
• aws --filters
• match PAN-OS command
• psql -c
• pkill -x
• Amazon CloudWatch Logs Insights
• Logs: ElasticSearch and OpenSearch
• yq
• logcli for Loki

 [[:alpha:]]

 [[:alnum:]]

[[:digit:]]

See also

• grep, grep -A, grep -B, grep -n, grep -H
• ack, ag, grep, egrep, fgrep, agrep, ngrep, pgrep, awk, sed, strings, tr, tail, mtail, git grep, wc, uniq, LogQL, findstr (Windows), rg, git-grep, cut
• include Cisco IOS command
• match PAN-OS command
• Select-String or sls in Powershell
• Linux logging, Cisco IOS logging

http://man7.org/linux/man-pages/man1/grep.1p.html