Unlock Hidden Linux Command Options: Practical Tips for ls, find, less, and More

1. ls command options

Use -S to sort files by size and combine with -r for reverse order. ls -lhS Reverse (largest to smallest):

ls -lhSr

-t: sort by modification time

ls -lht

Find files modified today:

ls -l / --time-style=+%D | grep `date +%D`

2. find command options

-size

is frequently used; other useful flags are highlighted below.

-iname

Case‑insensitive name matching.

find . -iname get_test

-name

Case‑sensitive name matching (contrast with -iname).

-type

Search by file type.

find . -type f
find . -type d

-empty

Locate empty files.

find . -type f -empty

-maxdepth

Limit recursion depth.

find /etc -maxdepth 2 -name passwd

3. less command options

Prefer less over vim for quick log viewing.

-N

Show line numbers.

less -N test.log

For small files, cat -n also displays line numbers.

+F

Equivalent to tail -f or tailf, continuously appending output.

less +F test.log

4. -r option examples

grep

Recursively search for a pattern in all files under a directory.

grep -r "xxx" /home

scp

Copy directories recursively.

scp -r [email protected]:/home/config/ .

5. -p option examples

mkdir

Create nested directories in one command.

mkdir -p /home/test/log

tar cp

Preserve file attributes while archiving.

tar -cpvzf mysql.tar.gz /var/lib/mysql

6. -C and -d options for extraction

Extract archives directly into a target directory.

tar

tar -xzvf tt.tar.gz -C /home

Alternative without -C:

cd /home
tar -xzvf tt.tar.gz

Or extract then move:

tar -xzvf tt.tar.gz
mv tt /home

unzip

unzip -d /home tt.zip