Linux Text Manipulation Cheat Sheet
Master text processing in Linux using essential commands like grep, sed, awk, cut, tr, and more.
1. grep - Search Text in Files
Find lines containing “error”
grep "error" logs.txt
Case-insensitive search
grep -i "warning" syslog.txt
Exclude matching lines
grep -v "DEBUG" logs.txt
2. sed - Stream Editor
Replace “Linux” with “Ubuntu”
sed 's/Linux/Ubuntu/' file.txt
Delete lines containing “error”
sed '/error/d' file.txt
Modify text inline
sed -i 's/old/new/g' file.txt
3. awk - Process Structured Text
Print second column
awk '{print $2}' data.txt
Filter rows where column 3 > 100
awk '$3 > 100 {print $1, $3}' data.txt
Use a custom delimiter (CSV)
awk -F, '{print $2}' data.csv
4. cut - Extract Text Columns
Extract characters 1-5
cut -c1-5 file.txt
Extract second column (default delimiter: tab)
cut -f2 data.txt
Extract third column from CSV
cut -d',' -f3 data.csv
5. tr - Translate or Delete Characters
Convert lowercase to uppercase
echo "hello world" | tr 'a-z' 'A-Z'
Remove digits
echo "abc123" | tr -d '0-9'
Replace spaces with underscores
echo "hello world" | tr ' ' '_'
6. sort - Sort Data
Sort alphabetically
sort names.txt
Sort numerically
sort -n numbers.txt
Sort in reverse order
sort -r names.txt
7. uniq - Remove Duplicate Lines
Remove consecutive duplicates
uniq sorted.txt
Count occurrences
uniq -c sorted.txt
8. paste - Merge Lines
Combine two files column-wise
paste file1.txt file2.txt
Use a custom delimiter (comma)
paste -d',' file1.txt file2.txt
9. tee - Output & Save to File
Display and save output
ls -l | tee output.txt
Append output to a file
ls -l | tee -a output.txt
10. wc - Count Lines, Words, Characters
Count lines
wc -l file.txt
Count words
wc -w file.txt
Count characters
wc -c file.txt
11. head & tail - View File Sections
Show first 10 lines
head file.txt
Show last 10 lines
tail file.txt
Monitor logs in real-time
tail -f /var/log/syslog
12. nl - Add Line Numbers
Number all lines
nl file.txt
13. rev - Reverse Text
Reverse each line
echo "hello" | rev
14. fold - Wrap Long Lines
Wrap text at 40 characters
fold -w 40 file.txt
15. column - Format Text into Columns
Format data into a table
column -t data.txt
Specify a custom delimiter (colon)
column -t -s ":" data.txt
Practical Example Log Analysis
Extract unique IPs from a log file, sort, and count occurrences
awk '{print $1}' access.log | sort | uniq -c | sort -nr