ealias README

Description

The ealias command is in effect a wrapper around emacsclient for the Bash shell. It’s a simple way of defining a shell function, which will in turn call a specific Emacs function with a number of given arguments. It gives a little bit of eshell feeling and is especially useful for mapping terminal-loving commands like man to their Emacs equivalents when using an M-x shell.

Installation

Somehow download the file ealias in some directory and source it either from your ~/.bashrc, for access in any shell, or your ~/.emacs_bash, if you prefer it only being active in the M-x shell.

Usage

After proper installation you should have access to a new command called ealias. See the output of

$ ealias --help

for a complete description and the Examples section below.

Environment Variables

There are a couple of variables which influence the behavior of the ealias command. They are listed in the following table and further described below.

For convenience the ealias options -w, -r and -e let you write, resp. read, resp. edit the file EALIAS_RC . This is just an easy way to write your possibly interactively defined aliases to a file and read them back in later.

Examples

A ealias definition looks pretty much like a normal alias, except it

• may contain a number of special format codes and
• it is called much like a function, i.e. it accepts parameter.

Let’s start with a simple example and redefine the man command, which is pretty useless in an M-x shell.

$ ealias man='man %*'

The %* construct takes the remaining arguments (in this case all) and concatenates them into a single string. We can examine what would be executed with the -n option.

$ man -n 3 printf
emacsclient --eval (man "3 printf")
$ man 3 printf
#<buffer *Man 3 printf*>

The next alias utilizes the diff command, which takes 3 arguments, namely the 2 files to find the differences for and which options to use.

$ ealias ediff='diff %^ %^ %*'

The %^ code pops an argument and wraps it, like all %-constructs, in double-quotes, thereby transforming the shell word into a Lisp string.

$ ediff -n file1 file2 -w -c
emacsclient --eval (diff "file1" "file2" "-w -c")

The last example finds a file and edits it as the root user.

$ ealias redit='find-file-other-window \"/sudo::$(readlink -f "$1")\"'

Note, that this alias uses regular parameters only. Since the whole expression is evaluated, we need to escape the quotes.

$ redit -n /etc/bashrc
emacsclient --eval (find-file-other-window "/sudo::/etc/bashrc")

See the file ealiasrc.example for more examples.