Experimental map shell function using xargs

gistfile1.sh

# Pull the username and password out of the xml file and into local vars
# Run the output through sed to escape & and _ characters for MySQL
# Note: the shell quoting here gets a little rough. The final command is:
# sed -e 's/[%_]/\&/g'
read dbuser dbpass <<<$(xmap \
    'xmlstarlet sel -t -v "//controller-config/database/@" '${XML_FILE}' \
    | sed -e '\''s/[%_]/\\\\&/g'\' \
    username password)

xmap.sh

function xmap() {
    # Run a shell command once for every argument passed. The first argument
    # should be a single-quoted string appropriate to pass to  sh -c.
    # For example:
    #       % xmap 'echo @' foo bar baz
    #       echo foo
    #       echo bar
    #       echo baz

    cmd=$1
    shift

    echo -n ${@} | xargs -r -d" " -I@ sh -c "${cmd}"
}