Linux in a Nutshell, Fourth Edition

Syntax

This subsection describes the many symbols peculiar to bash. The topics are arranged as follows:

• Special files

• Filename metacharacters

• Command-line editing

• Quoting

• Command forms

• Redirection forms

• Coprocesses

Special Files

File	Purpose
/etc/profile	Executed automatically at login.
$HOME/.bash_profile	Executed automatically at login.
$HOME/.bashrc	Executed automatically at shell startup.
$HOME/.bash_logout	Executed automatically at logout.
$HOME/.bash_history	Record of last session’s commands.
$HOME/.inputrc	Initialization file for reading input in an interactive shell.
/etc/passwd	Source of home directories for ~ name abbreviations.

Filename Metacharacters

Characters	Meaning
*	Match any string of zero or more characters.
?	Match any single character.
[ abc ...]	Match any one of the enclosed characters; a hyphen can be used to specify a range (e.g., a-z, A-Z, 0-9).
[! abc ...]	Match any character not among the enclosed characters.
[^ abc ...]	Same as [! abc ...].
{ str1 ,...}	Brace expansion: match any of the enclosed strings.
~ name	HOME directory of user name. With no name, HOME directory of current user.
~+	Current working directory (PWD).
~-	Previous working directory from directory stack (OLDPWD; see also the pushd built-in command).
~+ n	The nth entry in the directory stack, counting from the start of the list with the first entry being 0.
~- n	The nth entry in the directory stack, counting ...