#+TITLE: Shell
#+AUTHOR: Christopher James Hayward
#+EMAIL: chris@chrishayward.xyz

#+begin_src shell
ln -s ~/.local/source/dotfiles/config/shell/bashrc ~/.bashrc
ln -s ~/.local/source/dotfiles/config/shell/profile ~/.profile
#+end_src

* Bash
:PROPERTIES:
:header-args: :tangle ~/.local/source/dotfiles/config/shell/bashrc :results silent
:END:

Executed by bash for non-login shells. See ~/usr/share/doc/bash/examples/startup-files~ (in the package =bash-doc=) for examples.

If not running interactively, don't do anything.

#+begin_src shell
case $- in
    *i*) ;;
      *) return;;
esac
#+end_src

Don't put duplicate lines or lines starting with space in the history.

#+begin_src shell
HISTCONTROL=ignoreboth
#+end_src

Append to the history file, don't overwrite it.

#+begin_src shell
shopt -s histappend
#+end_src

For setting history length see ~HISTSIZE~ and ~HISTFILESIZE~.

#+begin_src shell
HISTSIZE=1000
HISTFILESIZE=2000
#+end_src

Check the window size after each command and, if necessary, update the values of ~LINES~ and ~COLUMNS~.

#+begin_src shell
shopt -s checkwinsize
#+end_src

If set, the pattern ="**"= used in a pathname expansion context will match all files and zero or more directories and subdirectories.

#+begin_src shell
#shopt -s globstar
#+end_src

Make less more friendly for non-text input files.

#+begin_src shell
[ -x /usr/bin/lesspipe ] && eval "$(SHELL=/bin/sh lesspipe)"
#+end_src

Set variable identifying the chroot you work in (used in the prompt below).

#+begin_src shell
if [ -z "${debian_chroot:-}" ] && [ -r /etc/debian_chroot ]; then
    debian_chroot=$(cat /etc/debian_chroot)
fi
#+end_src

Set a fancy prompt (non-color, unless we know we "want" color).

#+begin_src shell
case "$TERM" in
    xterm-color|*-256color) color_prompt=yes;;
esac
#+end_src

Uncomment for a colored prompt, if the terminal has the capability; turned off by default to not distract the user: the focus in a terminal window should be on the output of commands, not on the prompt.

#+begin_src shell
#force_color_prompt=yes
#+end_src

If we have color support; assume it's compliant with =Ecma-48 (ISO/IEC-6429)=.

#+begin_src shell
if [ -n "$force_color_prompt" ]; then
    if [ -x /usr/bin/tput ] && tput setaf 1 >&/dev/null; then
	color_prompt=yes
    else
	color_prompt=
    fi
fi
#+end_src

Lack of such support is extremely rare, and such a case would tend to support ~setf~ rather than ~setaf~.

#+begin_src shell
if [ "$color_prompt" = yes ]; then
    PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
else
    PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
fi
unset color_prompt force_color_prompt
#+end_src

If this is an xterm set the title to ~user@host:dir~.

#+begin_src shell
case "$TERM" in
xterm*|rxvt*)
    PS1="\[\e]0;${debian_chroot:+($debian_chroot)}\u@\h: \w\a\]$PS1"
    ;;
*)
    ;;
esac
#+end_src

Enable color support of ~ls~ and also add handy aliases.

#+begin_src shell
if [ -x /usr/bin/dircolors ]; then
    test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"
    alias ls='ls --color=auto'
    #alias dir='dir --color=auto'
    #alias vdir='vdir --color=auto'

    alias grep='grep --color=auto'
    alias fgrep='fgrep --color=auto'
    alias egrep='egrep --color=auto'
fi
#+end_src

Colored =GCC= warnings and errors.

#+begin_src shell
#export GCC_COLORS='error=01;31:warning=01;35:note=01;36:caret=01;32:locus=01:quote=01'
#+end_src

Some more ~ls~ aliases.

#+begin_src shell
alias ll='ls -alF'
alias la='ls -A'
alias l='ls -CF'
#+end_src

Add an ~alert~ alias for long running commands.

#+begin_src shell
alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'
#+end_src

Use like so:

#+begin_example
sleep 10; alert
#+end_example

You may want to put all your additions into a separate file like ~~/.bash_aliases~, instead of adding them here directly. See ~/usr/share/doc/bash-doc/examples~ in the =bash-doc= package.

#+begin_src shell
if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
fi
#+end_src

Enable programmable completion features. You don't need to enable this, if it's already enabled in ~/etc/bash.bashrc~ and ~/etc/profile~ sources ~/etc/bash.bashrc~.

#+begin_src shell
if ! shopt -oq posix; then
  if [ -f /usr/share/bash-completion/bash_completion ]; then
    . /usr/share/bash-completion/bash_completion
  elif [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
  fi
fi
#+end_src

* Profile
:PROPERTIES:
:header-args: :tangle ~/.local/source/dotfiles/config/shell/profile :results silent
:END:

Executed by the command interpreter for login shells.

This file is *not* read by bash, if ~~/.bash_profile~ or ~~/.bash_login~ exists. See =/usr/share/doc/bash/examples/startup-files= for examples. The files are located in the bash-doc package.

The default umask is set in ~/etc/profile~. For =SSH= logins, install and configure the =libpam-umask= package.

#+begin_src shell
#umask 022
#+end_src

If we're running =bash= make sure to include ~~/.bashrc~ if it exists.

#+begin_src shell
if [ -n "$BASH_VERSION" ]; then
    if [ -f "$HOME/.bashrc" ]; then
	. "$HOME/.bashrc"
    fi
fi
#+end_src

Add private bin directories to the ~$PATH~ (if they exist).
+ ~$HOME/bin~
+ ~$HOME/.local/bin~

#+begin_src shell
if [ -d "$HOME/bin" ]; then
    PATH="$HOME/bin:$PATH"
fi
if [ -d "$HOME/.local/bin" ]; then
    PATH="$HOME/.local/bin:$PATH"
fi
#+end_src
  
Add ~$HOME/go/bin~ to the ~$PATH~ if it exists.

#+begin_src shell
if [ -d "$HOME/go/bin" ]; then
    PATH="$HOME/go/bin:$PATH"
fi
#+end_src

Auto run =startx= on login if there's no display server running.

#+begin_src shell
if [ -z "${DISPLAY}" ] && [ "${XDG_VTNR}" -eq 1 ]; then
    exec startx
fi
#+end_src