Here is an OS X >= 10.6 Snow Leopard solution.
It Ignores .git and .svn folders and their contents. Also it won't leave a backup file.
export LC_CTYPE=C
export LANG=C
find . -not \( -name .svn -prune -o -name .git -prune \) -type f -print0 | perl -0ne 'print if -T' | xargs -0 sed -Ei 's/[[:blank:]]+$//'
As has been pointed out in a couple of other answers, the preferred method now is NOT to use smartindent, but instead use the following (in your .vimrc):
filetype plugin indent on
" show existing tab with 4 spaces width
set tabstop=4
" when indenting with '>', use 4 spaces width
set shiftwidth=4
" On pressing tab, insert 4 spaces
set expandtab
In your [.vimrc:][1] file:
set smartindent
set tabstop=4
set shiftwidth=4
set expandtab
The help files take a bit of time to get used to, but the more you read, the better Vim gets:
:help smartindent
Even better, you can embed these settings in your source for portability:
:help auto-setting
To see your current settings:
:set all
As graywh points out in the comments, smartindent has been replaced by cindent which "Works more cleverly", although still mainly for languages with C-like syntax:
:help C-indenting
Best Answer
I assume your questions is with regards to Java code. If that's the case, you don't actually need any extra plugins to accomplish 1). You can just go to Preferences -> Java -> Editor -> Save Actions and configure it to remove trailing whitespace.
By the sounds of it you also want to make this a team-wide setting, right? To make life easier and avoid having to remember setting it up every time you have a new workspace you can set the save action as a project specific preference that gets stored into your SCM along with the code.
In order to do that right-click on your project and go to Properties -> Java Editor -> Save Actions. From there you can enable project specific settings and configure it to remove trailing whitespace (among other useful things).
NB: This option has been removed in Eclipse Kepler (4.3) and following releases.
NB #2: The option seems to be back in Eclipse Luna -
Luna Service Release 1a (4.4.1)