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eventfd - A kernel-level event notification system.


The eventfd() function is used to create a file descriptor for event notification. This is similar to the poll and select system calls, but more efficient and with more features. It allows applications to setup application-level synchronization between processes or between threads. An eventfd descriptor can be used like a file descriptor, and can be monitored using poll, select or epoll, as well as flushing to user space when there is pending data. The initval parameter can be used to determine whether a specific eventfd descriptor has data available or not. The flags parameter is used to control the behavior of the eventfd descriptor.


  • initval:unsigned int[K] - Initial value. This is used to indicate whether a given eventfd descriptor has data available or not.
  • flags:int[K] - Flags controlling the behavior of the eventfd descriptor.

Available Tags

  • K - Originated from kernel-space.




kprobe + uprobe.


In order to provide efficient application-level synchronization, the eventfd system call is hooked so that the kernel can trigger an eventfd descriptor when necessary.

Example Use Case

The eventfd system call can be used in applications to create synchronization triggers. This can be useful in cases where synchronization between multiple threads is used, such as in the implementation of complex data structures.


No known issues.

Other synchronization functions, such as futex.

This document was automatically generated by OpenAI and needs review. It might not be accurate and might contain errors. The authors of Tracee recommend that the user reads the "events.go" source file to understand the events and their arguments better.