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waitpid - wait for a process to change its state


The waitpid() system call suspends execution of the calling process until a child process specified by pid argument has changed state. By giving the WNOHANG or WUNTRACED options to waitpid() call, the calling process can specify that it should return immediately if there is no process state change. The status pointer argument may be specified as NULL.


  • pid:pid_t - Specifies a set of child processes for which to wait.
  • status:int*[U] - A pointer to an integer into which status information about the child process will be stored. This can be NULL if the calling process is not interested in this information.
  • options:int - May be specified to include WNOHANG or WUNTRACED, which modify the behavior of the waitpid() system call.

Available Tags

  • U - Originated from user space (for example, pointer to user space memory used to get it)






Used to monitor usage of waitpid in the system.

Example Use Case

This event can be used to monitor and detect when a process with a specified pid has changed state.



  • fork()
  • execve()
  • signal()

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.