http://www.jaxelson.com/blog/?p=63#comment-204669976

dotfile-relink

#!/bin/bash
#
# Links files in this directory to the current users home directory.
#
# If the link already exists the file will be skipped unless the -f flag is given.
#
# Existing non-links are always skipped.

# BSD's realpath does not have the -f flag
real_path () {
    if [ -f $1 ]; then
        echo $(real_path $(dirname $1))/$(basename $1)
    else
        (cd $1 && pwd)
    fi
}

this=$(real_path $0)
SCRIPT_DIR=$(real_path $(dirname $0))
PREFIX=$HOME
symlink='ln -s'

while getopts "vfp:" flag; do
    case "$flag" in
        v) symlink=${symlink}v ;;
        f) symlink=${symlink}f ;;
        p) PREFIX=${OPTARG%/} ;;
    esac
done

errcode=0
for source in $SCRIPT_DIR/*; do
    [ $(real_path $source) = $this ] && continue

    target=$PREFIX/.$(basename $source)
    if [ -e $target -a ! -L $target ]; then
        errcode=1
        echo "skipping non-symlink $target"
    else
        $symlink $source $target
    fi
done
exit $errcode