Classical Problems on Synchronization: Reader-Writer | L 19 | Operating System | GATE 2022 CSE

[@saurabhtiwari287]

Sir, aapke ashirwaad se or aapki guidance se sabka bhala hoga. I guarantee it

[@aniketdas3406]

If there's someone like me who's struggling to understand how multiple processes can read without allowing any other process to write, it can be explained in this way: When the first reader process enters it decrements the wrt and makes it 0 so that no writer process can execute untill the last reader has done its job and signals wrt. Therefore, after the first reader process, other readers which will try to read concurrently will skip the if(readcount ==1) part since wrt is already decremented by the first read process and write() operations are halted. I hope it helped you :)

[@cruelgamer8351]

Okay but why there no code line to restrict readers in writer process

[@aspirant8409]

Start 7:10

[@Adityasharma-oe8zp]

And the guy who connected the tv to headphones was badly injured in confrontation🤣🤣🤣

[@Innov8mate]

Y does we can't block readers in write in function.

[@nirbhaykumarchaubey8777]

You Rock, Sir!

[@codeeasy17]

Nice explanation

[@krishbhat7466]

sir initially its written that multiple readers can access the file, but in code only one reader is allowed at a time and other reader wait at mutex. why?

[@Aditya-ie8ch]

we can't let mulitple readers access the readcount variable at the same time..thats why we gotta use wait(mutex)..however once the readcount++ is done and signal(mutex) too...other reader can now access the file..so we gotta use preemption at the end of 1st signal(mutex) for multiple readers to be able to read

[@latestsouthmoviehindi]

Ready to caught

[@uddipangoswami8427]

Sir in writer code why wait mutex is not taken before wait(wrt) ?

[@soumilyade1057]

cause wrt is a Binary semaphore, and readcount is a regular variable that can have a value of n...

[@AshishSinwer-o7e]

no need of that ... wait(wrt) will handle the blocking of other writer processes here and if there is a reading process wants to enter during the writer process , then the process will stuck in the wait(wrt) part of the reader process code as wrt = 0 at that time.

[@difflyfe23]

ready sir

[@kajalmondal9745]

♥♥