Bash – How to Switch to vi Editing Mode in Readline

bashreadline

I want to switch to vi editing mode in a readline environment. But I don't want to use 'set -o vi'. I want to temporarily switch using a keyboard shortcut. The man page says I can do this with M-C-j. But that doesn't work for me.

I'm using Ubuntu and an xterm. Doesn't work under gnome-terminal either.

Best Answer

I'd confirm that the keyboard mapping Meta+Control+j is in fact correct on your system. You can use this command to list all the keybinds for the various modes of Bash. On my system there wasn't a keybinding either.

$ bind -P| grep edit
edit-and-execute-command can be found on "\C-x\C-e".
emacs-editing-mode is not bound to any keys
vi-editing-mode is not bound to any keys

You can do the following so that when you type Esc+e it will toggle between the 2 modes.

$ set -o emacs
$ bind '"\ee": vi-editing-mode'
$ set -o vi
$ bind '"\ee": emacs-editing-mode'

The bind command now shows this:

in vi mode

$ bind -P |grep edit
edit-and-execute-command is not bound to any keys
emacs-editing-mode can be found on "\ee".
vi-editing-mode is not bound to any keys

in emacs mode

$ bind -P |grep edit
edit-and-execute-command can be found on "\C-x\C-e".
emacs-editing-mode is not bound to any keys
vi-editing-mode can be found on "\ee".

Now you can use Esc+e to toggle between the 2 different modes.

Related Solutions

Bash – How to Change $TERMINFO in bashrc Script

So after digging around some more, I found what's going on. RHEL5's build of bash doesn't use terminfo at all (why, who knows, it's Red Hat), it uses termcap. However, there is apparently another bash on the box which does use terminfo. This is why subshells and re-execing would work, as they would use the other bash, not the default one. I feel stupid for not noticing this.

This can be determined from comparing 2 commands:

# ldd "$BASH"
    linux-vdso.so.1 =>  (0x00007fff4f1fd000)
    libtermcap.so.2 => /lib64/libtermcap.so.2 (0x0000003e0bc00000)
    libdl.so.2 => /lib64/libdl.so.2 (0x0000003e07000000)
    libc.so.6 => /lib64/libc.so.6 (0x0000003e06c00000)
    /lib64/ld-linux-x86-64.so.2 (0x0000003e06800000)

# ldd `which bash`
    linux-vdso.so.1 =>  (0x00007fff643fd000)
    libncurses.so.5 => /usr/lib64/libncurses.so.5 (0x0000003e0d800000)
    libdl.so.2 => /lib64/libdl.so.2 (0x0000003e07000000)
    libc.so.6 => /lib64/libc.so.6 (0x0000003e06c00000)
    /lib64/ld-linux-x86-64.so.2 (0x0000003e06800000)

Noticing that one is linked against libtermcap, and the other against libncurses.

I should have specified that I was using RHEL here, as that's apparently the critical factor. Why they use termcap when pretty much everyone else in the world has abandoned it makes no sense, but there it is.

Bash readline: Key binding that executes an external command

Not all bash line editing is controlled from ~/.inputrc; much of it is configured via the bind builtin. In this case, you want something like

bind -x '"\C-gu":uptime'

in your ~/.bashrc.

Best Answer

Related Solutions

Bash – How to Change $TERMINFO in bashrc Script

Bash readline: Key binding that executes an external command

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