.. -*- coding: utf-8; -*-

=======

 Bash.

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.. contents::

   :local:

How override PS1, PS2?

======================

When loading bash read ~/.bash_profile and ~/.bashrc.

Put at end of these files::

  PS1='\u@\H$ '

When xterm start bash - it start as non-login. So ~/.bash_profile and ~/.bashrc

didn't read. To workaround this use::

  $ xterm -e bash -i -c "mc -x"

That make bash interactive and init file was readed.

Command history.

================

Bash allow accessing to command that you type previously. There are several

options to control command history behavior. Set corresponding variables in

your ~/.bashrc file (which is read by interactive shell)::

  #   ignorespace do not save lines that start with space

  #   erasedups all previous lines matching the current line to be removed from

  #             the history list before that line is saved

  export HISTCONTROL=igrorespace:erasedups

  export HISTIGNORE=" ?cd *":"e *":"sudo mv *":"sudo rm *":"sudo cp *":"sudo mkdir *":"sudo chmod *":"sudo chown *":ls:pwd:"vlc*"

There are another options, with default values (which satisfy my needs, so

I don't put they to ~/.bashrc)::

  export HISTFILE=~/.bash_history  # where is command history stored

  export HISTFILESIZE=500          # how many lines been in $HISTFILE

  export HISTSIZE=500              # how many lines been stored in bash process

mc (GNU Midnight Commander).

----------------------------

You can also set special history rules for mc subshell in ~/.mc/bashrc file.

Bash history.

=============

http://wiki.bash-hackers.org/scripting/bashchanges

  This article is an incomplete overview of changes to Bash over the time.

Exploring values

================

Display all or specific variable declarations::

  $ declare -p

  $ declare -p NAME1 NAME2

Display defined functions::

  $ declare -F

  $ declare -F NAME1 NAME2

Display function body::

  $ declare -f NAME