What are reentrant functions in multithreading?

What are reentrant functions in multithreading?

Reentrant functions are functions that can be interrupted in the middle of execution and safely called again ('re-entered') before the previous executions are complete. They are crucial in multithreading to avoid issues like data corruption.

Can you give me an example of a reentrant function?

Sure! A classic example is the strtok function in C, which is not reentrant. In contrast, a function that uses a static variable to keep track of its state would not be reentrant. A reentrant version would use parameters to maintain state instead.

Why are reentrant functions important in multithreading?

They are important because they allow multiple threads to execute the same function without interfering with each other, thus preventing race conditions and ensuring data integrity.

How can I make a function reentrant?

To make a function reentrant, avoid using static or global variables. Instead, use local variables or pass state information as parameters to ensure that each thread has its own context.