How can I use the same lock in both suspending and blocking code? `Mutex`seems to be only usable in suspend functions and `synchronized()`only in non-suspend.

Coroutines themselves are multi-threaded and have to do synchronization. They tend to spin wait for synchronization using

atomic.loop

from

kotlinx.atomicfu

. If the

synchronized

block is used for very fine grained synchronization such that blocking is insignificant if it even does happen, then I see no issue with using that from a coroutine. Don't suspend inside the block. You can use

runBlocking

to run coroutines (like

Mutex

) from a non-suspending context. Only use this from places where blocking is expected and do not call if the code is running on a dispatcher so don't use

runBlocking

from

<http://Dispatchers.IO|Dispatchers.IO>

. Avoid this if you can.