set code [ catch {exec which charmm } ]
if { $code != 0 } {
    set msg "Unsupported test: CHARMM executable not found in path"
    puts stdout $msg
    return $msg
}
#
# Example of using charmm selection tools 
# to generate a list of atom indices
#
charmm.preinit charmm_script=alamm.inp coords=charmm.c
#
charmm_acquire_selection selec_var=v selection= "ATOM * * C*"

puts stdout $v

# end charmm
charmm.shutdown

set check {5 7 11}

for {set i 0} {$i < 3} { incr i } {
    if { [ lindex $v $i ] != [ lindex $check $i ] } then {
	chemerr "wrong atom selection returned"
    }
}
return OK