MT_JINF/SMS.INJB - Get Job Information

Return information about a specific job.

Call Parameters Return Register Return Parameter
D0.B $02 D0.L Error code.
D1.L Id of job to get information for. D1.L Id of next job in tree.
D2.L Id of job at top of the tree. D2.L Parent job’s id for the job we enquired upon.
D3.L Unused. D3.L $000000pp = Active job’s priority. $FFFFFFpp = Suspended job’s priority.
A0.L Unused. A0.L Base address, JB_END, of the job.
A1.L Unused. A1.L Corrupted.


Error Code Description
ERR_NJ Invalid job id, in D1, on entry.


  • All registers not shown above are not used on entry and are preserved on exit.
  • This call can be used to scan the entire job tree, by initially calling it in a loop with D1.L = D2.L = zero, then on each subsequent call, leaving D1.L with the value returned, in D1.L, by the previous call. Eventually, D1.L will be returned as zero which indicates end of the tree.
  • If, on entry, D1.L = D2.L <> zero, then only that sub-tree will be scanned, not the entire tree.


The following shows the use of this call to scan the entire job tree :

start   moveq   #0,d1             ; Zero = SuperBasic.
        move.l  d1,d2             ; Job at top of tree also = SuperBasic.
loop    moveq   #SMS.INJB,d0      ; Or MT_JINF
        trap    #1                ; Fetch job information, sets D1.L = next job in tree.
        tst.l   d0                ; Check for errors.
        bne.s   <Error handler>   ; Oops, an error occurred.
        tsl.l   d1                ; Are we done yet?
        beq.s   done              ; Yes, no more jobs.
        <Do stuff here with info returned, but preserve D1.L and D2.L>
        bra.s   loop              ; Using D1 and D2's values from the trap, go and do next job.
done    ...