My task from the teacher is to create a program that solves the three problems using threads in Python: I start a little bit with it but I don't know how to complete it.
My task from the teacher is to create a
I start a little bit with it but I don't know how to complete it.
In the readers-writers problem there is a common resource where a group of actors called readers want to read from the resource and another group of actors called writers want to write to the resource.
The basic synchronization problem that needs to be solved is:
1. Mutual exclusion of the resource, where:
• only one writer may print at a time, and
• no writer may write while a reader is reading.
An ordinary mutex lock that is applied equally to all actors can solve this but will lead to only one actor being able to enter its critical section at a time.
The next problem that needs to be solved is therefore the following:
2. Several readers should be able to read the resource at the same time.
The last problem that needs to be solved is therefore the following:
3. As soon as a writer wants to write, new readers must not enter their critical section.1
Use the threading module for the actors: readers and writers.
The shared resource to be implemented is a text string.
Two different writers are continuously trying to write to the text string.
One writer is writing a date stamp all the way down to seconds.
The other writer writes the same thing, although the string writes backwards.
At least three identical readers simultaneously tries to continuously read the text string and print it to the standard output stream. See also Table for a summary.
| Actor | Total | Task |
| Reader | 3 | Reads and prints the text string to the standard stream. |
| Writer | 1 | Writes a date stamp, including seconds, to the text string. |
| Writer | 1 | Writes a reverse date stamp, including seconds to the text string |
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