15 Essential Linux Command-Line Tricks to Boost Productivity

Linux command line is a powerful tool for automation and efficiency; this article shares fifteen practical tips to boost productivity.

1. Quickly empty a file Use the shortest command: $ > access.log Other common methods include:

: > access.log

true > access.log

cat /dev/null > access.log

echo -n "" > access.log

echo > access.log

truncate -s 0 access.log

2. Generate a large file Use dd to create a 1 GB file: $ dd if=/dev/zero of=file.img bs=1M count=1024 3. Securely erase disk data Overwrite a disk with random data: $ dd if=/dev/urandom of=/dev/sda 4. Quickly create a bootable system disk Write an ISO image to a USB or disk: $ dd if=ubuntu-server-amd64.iso of=/dev/sdb 5. View a process’s running time Use ps -p PID -o etimes,etime to see elapsed time, or ps -p PID -o rss for memory usage.

$ ps -p 10167 -o etimes,etime
ELAPSED     ELAPSED
1712055 19-19:34:15

6. Dynamically monitor logs Tail a file with -f and stop on a pattern:

$ tail -f test.log
$ tail -f test.log | sed '/Failed/ q'

7. Convert timestamps Turn a Unix timestamp into a readable date:

$ date -d@1234567890 +"%Y-%m-%d %H:%M:%S"
2009-02-14 07:31:30

Get the current timestamp with date +%s.

8. Measure program execution time Use time to obtain real, user, and sys times and understand their differences.

$ time ./test
real    0m1.003s
user    0m0.000s
sys     0m0.000s

9. View ASCII table Run man ascii to see character codes.

10. Delete files with garbled names Find by inode and remove:

$ ls -i
138957 a.txt 138959 T.txt 132395 �?.txt
$ find . -inum 132395 -exec rm {} \;

11. Get your public IP address Simple curl queries:

$ curl ip.sb
$ curl ifconfig.me

12. Batch download web resources Use wget with filters:

$ wget -r -nd -np --accept=pdf http://fast.dpdk.org/doc/pdf-guides/

13. History command shortcuts Examples: !!, !N, !pw, !$.

14. Quickly search command history Press Ctrl+r and type a keyword.

15. Hide sensitive commands from history Prefix a command with a space so it is not recorded.