Local .vimrc files

If you can, it’s a good idea to set up your .vimrc file using conditionals so that it’s compatible on all of the systems with which you need to work. Using one .vimrc file enables you to include it as part of a centralised set of dotfiles that you can keep under version control.

However, if on a particular machine there’s a special case which means you need to load some Vim directives for that machine, you can achieve this by way of a local Vim file kept in .vimrc.local, only on one particular machine, and detecting its existence before attempting to load it in your master .vimrc file with the following stanza:

if filereadable(glob("~/.vimrc.local")) 
    source ~/.vimrc.local

As an example, on one of the nameservers that I manage, I wanted to make sure that the correct filetype was loaded when editing zone files ending in .nz or .au for New Zealand and Australian domains. The following line in .vimrc.local did the trick:

autocmd BufNewFile,BufRead *.au,*.nz set filetype=bindzone

If the .vimrc.local file doesn’t exist on any particular machine, Vim will simply not attempt to load it on startup.

Besides machine-specific code, this kind of setup may be advisable if you keep secret or potentially sensitive information in your .vimrc file that you wouldn’t want published to a public version control tracker like GitHub, such as API keys, usernames, machine hostnames, or network paths.

Packaging built software

The Debian package repository is enormous, and the Sid distribution is in most cases reasonably up-to-date, but it’s still sometimes desirable to build an application and install it into /usr/local when a packaged implementation either isn’t available or is too out of date, or if you’re involved in the development of a project and want to try out a fresh build that hasn’t been packaged yet.

The usual cycle of configuring, compiling, and installing many open-source applications for Unix-like systems applies here:

$ ./configure
$ make
# make install

The above is normally the approach taken to install code compiled on the machine, rather than through packages. One problem with this approach is that it doesn’t allow many of the advantages that a system running purely on packages does; dpkg -l will no longer give you a complete overview of all the system’s software, and to remove the software and its configuration files you may have to manually delete it rather than using apt-get purge.

Fortunately, there exists a tool called checkinstall to allow having the best of both worlds. After installing this tool via apt-get install checkinstall, you’re able to build a package for your locally built software according to the rules defined in its Makefile, and install that the same way as any other package.

Instead of typing make install, type checkinstall, and you will be prompted for details about the package, including its description, which is then built and installed. In this example, I’m compiling Vim from source, which works very well. I’ve also successfully installed tools like pam_ssh_agent_auth and tmux this way.

With this done, the package’s files are installed in /usr/local, and it appears in the list of installed packages along with my explanation of its contents:

$ ./configure
$ make
$ sudo -s
# checkinstall
**** Debian package creation selected ***

This package will be built according to these values:

0 -  Maintainer: [ Tom Ryder <tom@sanctum.geek.nz> ]
1 -  Summary: [ Custom build of latest Vim 7.3 ]
2 -  Name:    [ vim ]
3 -  Version: [ 2:7.4 ]
4 -  Release: [ 1 ]
5 -  License: [ GPL ]
6 -  Group:   [ checkinstall ]
7 -  Architecture: [ amd64 ]
8 -  Source location: [ vim ]
9 -  Alternate source location: [  ]
10 - Requires: [  ]
11 - Provides: [ vim ]
12 - Conflicts: [  ]
13 - Replaces: [  ]

Note that I’m assigning it a version number greater than the Debian repository’s vim package, which is a simple way to prevent it being replaced. You can also do this via the /etc/apt/preferences file to prevent replacement of all packages from the checkinstall group.

With this done, my custom build of Vim now shows in the package list, and its files are correctly installed in /usr/local:

# dpkg -l | grep vim
ii  vim  2:7.4-1 Custom build of latest Vim 7.3
# dpkg -S vim
vim: /usr/local/share/vim/vim73/bugreport.vim
vim: /usr/local/share/vim/vim73/plugin
vim: /usr/local/share/vim/vim73/ftplugin/postscr.vim
vim: /usr/local/share/man/it.UTF-8/man1/vim.1.gz

The .deb package built by checkinstall is also present in my build directory for me to keep for later, or for installation on another compatible server:

$ ls *.deb

It’s worth noting that checkinstall is not a Debian-specific tool; it works for other packaging systems like RPM and Slackware, too.