BashShell

Redirection

Redirection is used to manipulate input and output of commands

Standard input

to sort content of text file

Standard output

to create a new file that contains output of command

to append result to file that contains output of command

Standard error

to avoid standard errors output during command execution

Piping

 A pipe is used to send output of one command to be used as input for a second command

to filter results

to output results to a file and send them as an input to other commant tee is used

History

All user commands are written to file ~/.bash_history (~/.sh_history for AIX)

To see the list of commands from history

To clear history

To repeat command from history with id nn

Variables

Variables are convenient for scripting

To see default environments variables

To define variable

To read variable

Shortcuts

Bash Shortcut	Description
Ctrl+l	(smal (L) clear screen
Ctrl+u	wipe current command line
Ctrl+a	move to the beginning of a line
Ctrl+e	move to the endof a line
Ctrl+c	interrupt the current process
Ctrl+d	exit

Aliases

To use short link to a command an alias functin could be used

Config files

• Global
  • /etc/environment contains a list of variables that is processed while starting bash
• User specific
  • /etc/.profile.d additional user-specific configuration
  • ~/.bash_profile execute at the beginning of session
  • ~/.bash_logout execute at the logout
• Subshell configuration
  • ~/.bashrc for each new subshell

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