$PATH not updating

Question

I accidentally deleted my ~/.bashrc on my Ubuntu machine and now whenever I enter a command on terminal, it is giving me this error:

The command could not be located because '/usr/bin:/bin' is not included in the PATH environment variable.

I tried adding export PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin to ~/.bashrc, but I'm still facing the same issue.

I can export PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin on the terminal and it works fine, but I have to do it manually every time I open a new terminal. Is there a solution for this?

~/.bashrc contents :

case $- in
    *i*) ;;
      *) return;;
esac
HISTCONTROL=ignoreboth
shopt -s histappend
HISTSIZE=1000
HISTFILESIZE=2000
shopt -s checkwinsize
[ -x /usr/bin/lesspipe ] && eval "$(SHELL=/bin/sh lesspipe)"
if [ -z "${debian_chroot:-}" ] && [ -r /etc/debian_chroot ]; then
    debian_chroot=$(cat /etc/debian_chroot)
fi
case "$TERM" in
    xterm-color|*-256color) color_prompt=yes;;
esac
if [ -n "$force_color_prompt" ]; then
    if [ -x /usr/bin/tput ] && tput setaf 1 >&/dev/null; then
    # We have color support; assume it's compliant with Ecma-48
    # (ISO/IEC-6429). (Lack of such support is extremely rare, and such
    # a case would tend to support setf rather than setaf.)
    color_prompt=yes
    else
    color_prompt=
    fi
fi
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
case "$TERM" in
xterm*|rxvt*)
    PS1="\[\e]0;${debian_chroot:+($debian_chroot)}\u@\h: \w\a\]$PS1"
    ;;
*)
    ;;
esac
if [ -x /usr/bin/dircolors ]; then
    test -r ~/.dircolors && eval "$(dircolors -b ~/.dircolors)" || eval "$(dircolors -b)"
    alias ls='ls --color=auto'
    #alias dir='dir --color=auto'
    #alias vdir='vdir --color=auto'
    alias grep='grep --color=auto'
    alias fgrep='fgrep --color=auto'
    alias egrep='egrep --color=auto'
fi
alias ll='ls -alF'
alias la='ls -A'
alias l='ls -CF'
alias alert='notify-send --urgency=low -i "$([ $? = 0 ] && echo terminal || echo error)" "$(history|tail -n1|sed -e '\''s/^\s*[0-9]\+\s*//;s/[;&|]\s*alert$//'\'')"'
if [ -f ~/.bash_aliases ]; then
    . ~/.bash_aliases
fi
if ! shopt -oq posix; then
  if [ -f /usr/share/bash-completion/bash_completion ]; then
    . /usr/share/bash-completion/bash_completion
  elif [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
  fi
fi
export PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin
export POCL_DEBUG=0
export POCL_DEVICES=rsim
export POCL_CACHE_DIR=$HOME/temp_pocl
export REDEFINE_HOME=$HOME/redefine/
export POCL_LEAVE_KERNEL_COMPILER_TEMP_FILES=1
export PATH=$PATH:/home/harry/redefine/bin/riscv32-gcc/bin
export LLVM_PATH=$HOME/llvm-project/build/bin
export PATH=$HOME:$LLVM_PATH

Answer 1

First of all, you should remove your PATH declarations from ~/.bashrc. You don't want these to be re-run each time you open a new shell! This sort of global variable definition belongs in ~/.profile or, if the file exists, ~/.bash_profile.

Now, the problem you are facing is caused by the multiple PATH declarations you have which are overwriting each other. These are the relevant lines:

export PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin
export PATH="$PATH":/home/harry/redefine/bin/riscv32-gcc/bin
export LLVM_PATH="$HOME"/llvm-project/build/bin
export PATH="$HOME:$LLVM_PATH"

Those are 4 commands, each of which will be run sequentially. Let's see what happens if we run them in a terminal:

$ export PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin
$ echo "$PATH"
/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin
$ export PATH="$PATH":/home/harry/redefine/bin/riscv32-gcc/bin
$ echo "$PATH"
/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin:/home/harry/redefine/bin/riscv32-gcc/bin
$ export LLVM_PATH="$HOME"/llvm-project/build/bin
$ export PATH="$HOME:$LLVM_PATH"
$ echo "$PATH"
/home/terdon:/home/terdon/llvm-project/build/bin

As you can see above, your final export command overwrites the previous changes you had made and sets PATH to only contain your $HOME dir (which doesn't make sense, you don't want your $HOME in your PATH!) and your $LLVM_PATH. What you wanted to do was add the $LLVM_PATH to $PATH, so you should instead have this:

export PATH=/bin:/usr/bin:/usr/local/bin:/sbin:/usr/sbin:/home/harry/redefine/bin/riscv32-gcc/bin
export LLVM_PATH="$HOME"/llvm-project/build/bin
export PATH="$PATH:$LLVM_PATH"

So, delete all PATH definitions from your ~/.bashrc and add the three lines above to your ~/.profile instead.