Try It Yourself - SyntaxStudy Editor

HTML / CSS / JS

# Basic pattern search
grep "error" /var/log/syslog

# Case-insensitive search
grep -i "error" /var/log/syslog

# Show line numbers
grep -n "failed" /var/log/auth.log

# Invert match — lines NOT containing pattern
grep -v "^#" /etc/ssh/sshd_config   # Show non-comment lines

# Count matching lines
grep -c "GET" /var/log/nginx/access.log

# List only filenames that contain a match
grep -rl "password" /etc/

# Recursive search with context (2 lines before and after)
grep -rn -C 2 "TODO" /var/www/html/

# Extended regex — match multiple patterns
grep -E "error|warning|critical" /var/log/syslog

# Match whole words only
grep -w "root" /etc/passwd

# Fixed string search (no regex, faster)
grep -F "192.168.1.1" /var/log/nginx/access.log

# Show only the matched portion, not the whole line
grep -o "[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}" /var/log/nginx/access.log | sort | uniq -c | sort -rn

# Exclude binary files
grep -I "pattern" /usr/bin/*

# Search with colour highlighting
grep --color=auto "FAILED" /var/log/auth.log