Soon I will be bringing an explanation and tutorial to the huddled masses of command line Linux users that have not had the joy of utilizing bash completion for applications.

Bash completion offer hints for arguments. An example of this would be using Gentoo's "equery" for package property information. Alright, I want to know which applications have an "opengl" use flag. So after installing app-shells/bash-completion and app-shells/gentoo-bashcomp I can type:

Which shows:

belongs   check     depgraph  glsa      list      stats     which     
changes   depends   files     hasuse    size      uses      

It looks like I want to use the "hasuse" argument to figure out which packages have an opengl use flag. I can even type part of the command, like has[tab] and it will complete to hasuse.

[egon@bigred ~ ]$ equery hasuse opengl
[ Searching for USE flag opengl in all categories among: ]
 * installed packages
[I--] [ -] app-emulation/emul-linux-x86-xlibs-20080810 (0)
[I--] [  ] media-libs/xine-lib-1.1.16.3 (1)
[I--] [  ] media-libs/libsdl-1.2.13-r1 (0)
[I--] [  ] games-emulation/sdlmame-0.129 (0)
[I--] [  ] media-video/mplayer-1.0_rc2_p20090731 (0)
[I--] [  ] gnome-extra/gnome-screensaver-2.24.1-r1 (0)
[I--] [  ] x11-libs/fox-1.6.36 (1.6)
[I--] [ ~] x11-libs/cairo-1.8.8 (0)