Editing command line with $EDITORFri, Aug 6, 2010
Recently, I’ve been working on a huge command line that I wanted to edit over and over. However, the problem was that I didn’t want to use the prompt to edit the command. It took me a while to realize what I wanted, but finally, I realized that mostï»¿ of the Emacs bindings are very useful in bash, so I went to work.
I use VIM for all of my editing when I can. I don’t much care for Emacs, but since bash uses the bindings, it’s good to know a few of the commands. Like Ctrl+k, Ctrl+u, Ctrl+e, Ctrl+a (try them out with text on the bash command if you don’t know what they do…). The thing is, the default editor in many of my CentOS systems at work is Emacs. I clearly didn’t want that, so I had to change two variables in my ~/.bashrc file. It now looks better:
$ cat ~/.bashrc<br />
.. snip ..<br />
export EDITOR VISUAL<br />
.. snip ..
After setting these variables up, it’s very easy to edit the command line with vim. First, source the ~/.bashrc file.
$ source ~/.bashrc
Then bring up the command to edit:
$ yum remove -y NetworkManager.i?86 NetworkManager-glib.i?86 alsa-lib.i?86 apr.i?86 aspell.i?86 audit-libs.i?86 coolkey.i?86 cracklib.i?86 cryptsetup-luks.i?86 cyrus-sasl-lib.i?86 cyrus-sasl-plain.i?86 db4.i?86 dbus-glib.i?86 dbus-libs.i?86 device-mapper.i?86 e2fsprogs-libs.i?86 ecryptfs-utils.i?86 expat.i?86 fipscheck.i?86 freetype.i?86 giflib.i?86 glib2.i?86 gpm.i?86 hal.i?86 java-1.6.0-openjdk.i?86 keyutils-libs.i?86 krb5-libs.i?86 libICE.i?86 libSM.i?86 libX11.i?86 libXau.i?86 libXdmcp.i?86 libXext.i?86 libXi.i?86 libXt.i?86 libXtst.i?86 libXxf86vm.i?86 libaio.i?86 libcap.i?86 libdaemon.i?86 libdrm.i?86 libgcc.i?86 libgcrypt.i?86 libgpg-error.i?86 libhugetlbfs.i?86 libjpeg.i?86 libpng.i?86 libselinux.i?86 libsepol.i?86 libstdc++.i?86 libtermcap.i?86 libusb.i?86 libutempter.i?86 libvolume_id.i?86 mesa-libGL.i?86 mkinitrd.i?86 ncurses.i?86 neon.i?86 nspr.i?86 nss.i?86 nss_db.i?86 nss_ldap.i?86 numactl.i?86 openldap.i?86 openssl.i?86 openssl-devel.i?86 pam.i?86 pam_ccreds.i?86 pam_krb5.i?86 pam_passwdqc.i?86 pam_pkcs11.i?86 pam_smb.i?86 parted.i?86 readline.i?86 redhat-lsb.i?86 sqlite.i?86 tcp_wrappers.i?86 wireless-tools.i?86 zlib.i?86
As can be seen, this is pretty long and cumbersome. It’d be nice to be able to edit the line without having to use bash, plus, if I accidentally mistype and hit ‘Enter’, it could be executed before the command is ready. To edit the command, hit the following:
The command will then be opened in your $EDITOR (probably /usr/bin/vim if you followed the instructions above). Edit away, when you save and quit (:wq in VIM), the command will be executed. If you don’t want to execute the command after all, just quit without saving (:q in VIM).