NAME

alias - define or display aliases

 SYNOPSIS

alias [alias-name[=string] ...]

 DESCRIPTION

The alias utility creates or redefines alias definitions or writes the values of existing alias definitions to standard output. An alias definition provides a string value that replaces a command name when it is encountered. See Alias Substitution .

An alias definition affects the current shell execution environment and the execution environments of the subshells of the current shell. When used as specified by this specification, the alias definition will not affect the parent process of the current shell nor any utility environment invoked by the shell. See Shell Execution Environment .

 OPTIONS

None.

 OPERANDS

The following operands are supported:

alias-name

Write the alias definition to standard output.

alias-name=string

Assign the value of string to the alias alias-name.

If no operands are given, all alias definitions will be written to standard output.

 STDIN

Not used.

 INPUT FILES

None.

 ENVIRONMENT VARIABLES

The following environment variables affect the execution of alias:

LANG

Provide a default value for the internationalisation variables that are unset or null. If LANG is unset or null, the corresponding value from the implementation-dependent default locale will be used. If any of the internationalisation variables contains an invalid setting, the utility will behave as if none of the variables had been defined.

LC_ALL

If set to a non-empty string value, override the values of all the other internationalisation variables.

LC_CTYPE

Determine the locale for the interpretation of sequences of bytes of text data as characters (for example, single- as opposed to multi-byte characters in arguments).

LC_MESSAGES

Determine the locale that should be used to affect the format and contents of diagnostic messages written to standard error.

NLSPATH

Determine the location of message catalogues for the processing of LC_MESSAGES .

 ASYNCHRONOUS EVENTS

Default.

 STDOUT

The format for displaying aliases (when no operands or only name operands are specified) is:

"%s=%s\n", name, value

The value string will be written with appropriate quoting so that it is suitable for reinput to the shell. See the description of shell quoting in Quoting .

 STDERR

Used only for diagnostic messages.

 OUTPUT FILES

None.

 EXTENDED DESCRIPTION

None.

 EXIT STATUS

The following exit values are returned:

0

Successful completion.

>0

One of the name operands specified did not have an alias definition, or an error occurred.

 CONSEQUENCES OF ERRORS

Default.

 APPLICATION USAGE

None.

 EXAMPLES

1. Change ls to give a columnated, more annotated output:

   
   alias ls="ls -CF"
   
   

2. Create a simple "redo" command to repeat previous entries in the command history file:

   
   alias r='fc -s'
   
   

3. Use 1K units for du:

   
   alias du=du\ -k
   
   

4. Set up nohup so that it can deal with an argument that is itself an alias name:

   
   alias nohup="nohup "
   
   

 FUTURE DIRECTIONS

None.

 SEE ALSO

Function Definition Command .