realbjornroden/unix

work in progress

Proper Desktop Unix

darwin aka macosx
darwin-xnu kernel
Shell and Utilities volume of IEEE POSIX.1-2017

Proper Command Line SHELL

Install Homebrew on macosx

$ curl -fsSL -o install.sh https://raw.githubusercontent.com/Homebrew/install/master/install.sh
$ chmod +x ./install.sh
$ ./install.sh

Install KornShell on macosx

$ brew install ksh

Enable ksh as default shell for the user

$ chsh -s /bin/ksh

Configure ~/.profile

export PS1="\${PWD#*/*/*/} \$ "
export VISUAL=/usr/bin/vi
export EDITOR=/usr/bin/vi

Proper visual EDITOR

vi & vim

Proper TOOLS

gnu tool packages

How To

Copy-Paste text in Terminal

1. Select text to copy > CTRL-C > Put cursor at insertion point > CTRL-V, and the text is copy-pasted to the insertion point
2. Put cursor at insertion point > Select text to copy, and then release the mouse/trackpad pressure > Select the marked text and "pull" it slightly until the colored circle with "+" sign appear (direction not important) > Release the mouse/trackpad pressure, and the text is copy-pasted to the insertion point

Configuring a minimalistic but most useful command line prompt

• For workstation only, don't need username, hostname or wasting a separate line with color time and other non-important information at each and every ENTER

• For directory structures, in a hierarchical organized filesystems, consider using Partial Relative Path display instead of Absolute Path display (when confused pwd)

  $ pwd
  /home/bjro
  $ export "PS1="\${PWD#*/*/*/} \$ "
  /home/bjro $ code/unix
  code/unix $ pwd
  /home/bjro/code/unix
  code/unix $ cd -
  /home/bjro $ pwer
  /home/bjro
  

• For multi-user hosts only, where it is common to slip around/jump between hosts over TCP connections, and substitute/change user id (and real rooters don't clobber "/")

  $ export "PS1="$LOGNAME@$(hostname -s):\${PWD#*/*/*/} \$ "
  bjro@server123:code/unix $ ssh honeyp321
  bjro@honeyp321:code/unix $ su - root
  root@honeyp321:/ $ echo $LOGNAME $(hostname -s) $PWD
  root honeyp321 /
  

  For ZSH, PS1 can be defined similarly (~/.zshrc)

  $ export PS1="%n@%m:%2~%(!.#.\$) "
  

• Defaulting command line editor and command line visual editor (invoked with ESC-v to edit long command line code), add to ~/.profile

  export VISUAL=/usr/bin/vi
  export EDITOR=/usr/bin/vi
  

• Load environment variables and aliases etc

  • use dot . not source to load, too much to type without functional difference and thus contradict the "unix ethos"

    $ grep PS1 ~/.profile
    export "PS1="\${PWD#*/*/*/} \$ "
    $ . ~/.profile
    code/unix $
    

• Rename a file with spaces in the name, if it's the only file in the directory (NB. on some shell's need to escape each space separately)

  $ mv * $(echo *|tr ' ' '_')
  

VI editor tips & trix

posix-vi and command line editing features (ESC one time to enter command mode, until insert/append/substitute/change command, then ESC again to get back to command mode). In interactive shell, ESC-v will enter into $VISUAL editor for the command line (save & exit will execute the edited command).
. - Repeat last command
k - Up one line
j - Down one line
w - Right one word
b - Left one word
l - Right one character
h - Left one character
Y - Copy one line
p - Paste copy buffer to after cursor line
P - Paste copy buffer to before cursor line
i - Insert at cursor
I - Insert at begining of line
a - Append after cursor
A - Append after end of line
s - Substitute one character at cursor
S - Substitute the whole line
u - Undo last command
x - Delete one character at cursor
X - Delete one character at cursor move left
dw - Delete one word from cursor forward
db - Delete one word from cursor backward
cw - Change one word from cursor forward
cb - Change one word from cursor backward
. - Repeat the last command, such as change the case of the current charcter
~ - Change the case of the current chararcter to the opposite (UPPER > lower || lower > UPPER)
ZZ - Save file and exit
/ - Enter search mode (down)
? - Enter search mode (up)
: - Enter line command mode
:w - Enter line command mode, and save file
:wq - Enter line command mode, and save file and exit
:wq! - Enter line command mode, and write quit forced
:r /etc/motd - Enter line command mode, and read the content of the file "/etc/motd" into the editor (at the cursor)
:!ls - Enter line command mode, and run the "ls" command in a subshell
:r!ls - Enter line command mode, and run the "ls" command in a subshell, and read the the output into the editor (at the cursor)
:%!sort - Enter line command mode, and for all lines in the file "%", run the "sort" command in a subshell and replace the content of the file
:%s/^XXX/YYY/g - Enter line command mode, and for all lines in the file "%", change all "XXX" on all lines which start with "XXX" to "YYY"
:%s/$/;/g - Enter line command mode, and for all lines in the file "%", add a ";" at the end of each line
:2,$!sort - Enter line command mode, and for all lines from 2 until end of file "2,$", run the "sort" command in a subshell and replace the content of the file (if the file has a header line)
:!rm % - Enter line command mode, and run the "rm" command on the edited filename "%"
:e /etc/motd - Enter line command mode, and open the file /etc/motd into the editor
:n - Enter line command mode, and switch the visual editor to the next file (when editing multiple files)
:e# - Enter line command mode, and switch the visual editor to the previous file (when editing multiple files), toggling :e# flips the editor between two files
:set - Enter line command mode, and show editor configuration settings
:map - Enter line command mode, and show editor key-action mapping

• Optional initialization command file ~/.exrc, in this case set the tabstop to 4 instead of default 8

set tabstop=4
set expandtab " this is for Python & YAML, to expand each tab to spaces