Your locale tells the computer your location, preferred time-and-date format, standard language, papersize, et c. A list of supported locales is available at /usr/share/i18n/SUPPORTED

See a full list with:

1cat /usr/share/i18n/SUPPORTED

Take the first portion to generate full locale information for a region:

1 …

Type

type shows what kind of thing you're running, be it an alias, function, or binary program.

1type cmus

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  loading="lazy"
  decoding="async"
  alt="where is cmus?"
  
    class="image_figure image_internal …</picture></figure></p>

Firstly, your ls is probably aliased to something.

Check it with:

1alias ls

If the prompt shows some alias, then start by removing it:

1unalias ls

Now we can begin.

Check the most recently modified file:

1ls -t

Reverse this with tac to see the file which has been unmodified the longest:

1ls -t | tac

Group files by …

Proccesses

See running items in current terminal with

1ps

or more with

1ps -a

Or the entire system with

1ps -e

Or the entire system with more information, BSD style, with:

1ps aux

And then search for a particular program with

1ps aux | grep cmus

Jobs

Pause a job with ^z. Put it in the background with the '&' …

This & That

Refer to 'that last thing', and 'the first thing':

1fortune -l > file1
2cat !$  | tr -d u
3diff !^ !$

NB: this can go wrong:

1ls -l file1 file2
2cat !^

Done

<C-d>

• If you have a command, Control + d will execute the command.
• If you have nothing, exit.

Input Run-Commands (~/.inputrc)

Alias …

A soft link is a file which says how to go to another file. When a program encounters a soft link, it will make a guess at whether it should ignore it, or try to get to that file.

To make a soft link to a file in the current directory, linking is easy:

1fortune > $file_1
2ln -s $file_1 $link_1

Now imagine your …

Making a Swap File

1cd /var/cache/

1sudo dd if=/dev/zero of=swapfile bs=1K count=4M

This creates a swapfile of (1k x 4M) 4 Gigs. Change 4M to XM for an XGig swap.

1sudo chmod 600 swapfile

1sudo mkswap swapfile

1sudo swapon swapfile

Test it's working with top

1top -bn1 | grep -i swap

or:

1echo "/var/cache/swapfile …

systemd

Set time to synchronize with an ntp server:

1timedatectl set-ntp true

This info stays in /usr/share/zoneinfo.

Local Time

Local time is kept in /etc/localtime.

According to Dave's LPIC guide, you can set the local time by making asymboling link from your timezone to /etc/localtime, as so:

1sudo ln -sf …

The tree utility outputs a full listing of everything in your current directory, and those below.

• Just directories: tree -d
• Output colour to less: tree -C --info | less -re
• Ignore files in the .gitignore file: tree --gitignore

You can place information about the files in a directory to use with the tree --info …

Basic Information

Let's get some entries with 'getent', e.g. passwd or group.

1getent passwd

1getent group

Obviously:

1getent shadow

Examples

1sudo adduser maestro 

add user 'maestro'

This depends upon the settings in the /etc/default/useradd file and /etc/login.defs

1sudo useradd -m pinkie 

add user 'pinkie' with a …