Question

3 char circularBuffernew char BUFFER SIZE, // buffe:r 4 int writerPosition-0; // next slot to write to 5 int readerPosition0; // next slot to read from 6 int occupiedSTots-0 / number of slots with data // condition variable // condition variable 7Condition hasData; 8 Condition hasSpace; 10 / monitor entry called by producer to write data 11 monitorEntry void putChar ( char slotData ) 12 13 wait on condition variable hasSpace if buffer is full 14 if ( occupiedSTots#BUFFER-SIZE) 15 16 17 18 wait hasSpacewait until hasSpace is signaled ) // end if // write character to buffer circularBuffer [ writerPosition ] = slotData ; ++occupiedslots; // one more slot has data writerPosition_ (writerPosition + 1) % BUFFER SIZE; signal( hasData ; // signal that data is available 20 21 23 24 / end putChar 25 26 I/ monitor entry called by consumer to read data 27 monitorEntry void getChar ( outputParameter slotData ) 28 29 30 31 32 // wait on condition variable hasData if the buffer is empty if occupiedslots 0) wait hasData; 1/ wait until hasData is signaled ) // end if 34 35 3 6 37 38 39 40 // read character from buffer into output parameter slotData slotData = circularBuffer [ readPosition ]; occupiedslots-/ one fewer slots has data readerPosition = (readerPosition 1) % BUFFER SIZE; signal ( hasSpace I signal that character has been read // end getChar Figure 6.2| Monitor pseudocode implementation of a circular buffer. (Part 2 of

I. Which Statements modify a shared critical variable to indicate that another slot in the buffer is available?

J. Describe an application of a monitor- controlled circular buffer within a Operating System.

Answer 1

Solution. eh Stoterients nodfy a shored Cvitica voriable to indicote that onothe slot n the Suefer i avaliable tThe concuTent access to a shared esou Ce A ON the The Second line Is Deline tot nitialisokion ot the ovadiable Buffed Descnbe on opplteation of o roniy-controlted *The cisalow Buprings d iméuan tafien hould be 0 HOTİ HUH Size be cdopted for o queue. expanding Qeues, a finked ist opriock ay be preferted instead

The uteel mopert o a civGulay Geffer tHat is Does hot heed to haue 's lement shfled avond uben oreConouMed IS Gsfile a slandond, Non-Civufer s uel Suited *Some ditunthiont, over toriting CiCulor Bripteor can be uned emmpe Ih Nulinedia 3t the s s used as the Bounded Bufor th the frodseo con6uesx probler 10vertorite otd data the consumer r.Soundcosd is unable to hometoily keep up. also, theoNe are of lossless Dotn Cerpresion algenithMs operakes on the osSumpo that trings Seeh toe ecently in o oata Stseom ore Nore likely to occu oon tn the tomfeeniations tore he Nost Yecent Dato tn a Cicular Baffes "THE END