knit Rmd into md and html

knit.sh

#!/bin/bash

usage()
{
    cat <<EOF>&2
usage: $0 <name>
knits ${name}.Rmd into ${name}.md and ${name}.html
EOF
    exit
}

err()
{
    echo $* >&2
    exit
}

[ $# -eq 0 ] && usage
name=$1
[ -f ${name}.Rmd ] || err "Cannot find or read ${name}.Rmd"

trap "rm -f /tmp/knit.$$.R" SIGINT SIGTERM

cat <<EOF>/tmp/knit.$$.R
require(knitr)
require(markdown)
knit('${name}.rmd','${name}.md')
markdownToHTML('${name}.md','${name}.html')
browseURL(paste('file:///', file.path(getwd(), '${name}.html'), sep=''))
EOF

R CMD BATCH /tmp/knit.$$.R
rm -f /tmp/knit.$$.R