more portable print_time, notably for occasional negative (!) elapsed time of theory_timing;
#!/bin/bash
#
# self-update of the administrative isabelle repository
#
# Need to copy this file manually to $HOME/cronjob in order to
# avoid overwriting the running self_update by itself!
source "$HOME/.bashrc"
cd "$HOME/cronjob"
mkdir -p run log
hg -R isabelle pull "http://isabelle.in.tum.de/repos/isabelle" -q || echo "self_update pull failed"
hg -R isabelle update -C -q || echo "self_update update failed"