it must not run for any extended period of time, because udev is effectively paused while these programs are running. One workaround for this limitation is to make sure your program immediately detaches itself.
echo -e "`asterisk -x "core show hints"`"
yum -y groupinstall development tools
./configure --enable-ssl --enable-ssl-crtd --prefix=/opt/squid
make all
make install
echo 1 > /sys/class/scsi_disk/x:x:x:x/device/rescan
echo 1 > /sys/class/block/xxx/device/rescan