opensm-3.2.1-1.fc10.x86_64 on an fc9 up-to-date system.

opensm forks itself.  You can't do this:
    $prog $OPTIONS > /dev/null 2>&1 &
    OSM_PID=$!
Try something like:
    $prog $OPTIONS > /dev/null 2>&1 &
    sleep 1
    OSM_PID=$(pidofproc $prog)

These test expressions always err:
    while [ $cnt -lt 6 -a checkpid $OSM_PID -eq 0 ]; do
maybe something like:
    while [ $cnt -lt 6 ] && checkpid $OSM_PID; do
(two spots).

Missing ACTION, I hacked in a line at the bottom:
ACTION=$1
case $ACTION in