watchmu

#!/usr/bin/env bash
################################################################################
# watchmu - this script launches mupdf with whatever arguments are provided and
# then automatically reloads the PDF whenever it changes on disk.  Eventually
# mupdf is supposed to support automatic reloads natively, but for the time
# being this hack works.  This is nice for automatically updating PDF output
# from latex.
#
# (If you've never used mupdf before, it's a great lightweight PDF viewer.
# see http://www.mupdf.com/ for details)
#
# Dependencies:
#  - inotifywait: https://github.com/rvoicilas/inotify-tools
#  - xdotool: http://www.semicomplete.com/projects/xdotool/
#
# Usage:
#   watchmu ./my_thesis.pdf
#   watchmu -r92 ~/stuff/important_paper.pdf
#
# Version 2
# Matthew Malensek <matt@malensek.net>
################################################################################

kill_mu() {
    kill ${mupid}
    exit $?
}
trap kill_mu SIGINT SIGTERM

wait_mu() {
    inotifywait -qq -e close ${@}
    while inotifywait -qq -t1 -e close ${@}; do :; done
}

mupdf ${@} &
mupid=${!}
filename="$(basename ${!#})"

while true; do
    if ! ps -p ${mupid} &> /dev/null; then
        break
    fi

    wait_mu ${!#}
    xdotool search --pid ${mupid} --name "${filename}" key 'r' &> /dev/null
done