| OCR Text |
Show 95 slot associated with the dovice there is either an Ü or a data descriptor poirting to a segment which contains data to go out or data coming in. The figure shows an execution ot the statement: printer 2 * "al3 = " # ai3# " b22=',#b22; Since no format of any Kind has been specified, a FLEX free-format is assumed. As the concatenations are executed, a scratch segment is created in the usual way to contain the generated string. When the %" is executed it first looks at the description for the storand. It is marked as a temporary and therefore only a name transfer is needed rather than a copy. This is done into the slot in the I/O process stack which is now marked active. Some time in the near future the I/O system will deliver an interrupt saying that printer 2 is free. The "printer 2" device number (in this case: 4) finds the data description in the stack indicating that something has to go out. This is set up and that data is squirted out on the channel coax. The "printer 2" slot is now marked empty and life goes on as before. If the above FLEX statement were in a loop for printing out consequentively generated values of al3 and B2?, it might very well be possible that another "printer 2" assignment might be made before the previous line was |
