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rt_sigtimedwait_time32 - wait synchronously for queued signals arising within a given time


rt_sigtimedwait_time32 is a system call that allows waiting for one of the pending signals occurring in the signal set uthese with a timeout of uts, which is rounded up to the system clock granularity (specified by uts). The signal's number and its associated uinfo are returned in the uinfo argument if available. sigsetsize is used to indicate size in bytes of the signal set pointed by uthese. Status of the signal for which the call was unblocked is returned. The time is limited by the uts->tv_sec and uts->tv_nsec arguments. If timeout is set to 0 and no signals are present on the queue, then this will cause an error.

This system call provides an easy to use way to wait for signals that arrive over a short period of time with the benefit of minimizing the chances of missing them.


  • uthese:sigset_t* - pointer to a signal set containing the signals which are to be waited for.
  • uinfo:siginfo_t*[K] - pointer to a siginfo_t structure to store the information about the signal, may be NULL.
  • uts:struct old_timespec32*[K] - a structure that specifies the end time for the timeout, may be NULL.
  • sigsetsize:size_t[K] - number of bytes in the signal set pointed to by uthese.

Available Tags

  • K - Originated from kernel-space.
  • U - Originated from user space (for example, pointer to user space memory used to get it)
  • TOCTOU - Vulnerable to TOCTOU (time of check, time of use)
  • OPT - Optional argument - might not always be available (passed with null value)






This function is hooked to measure the time it takes for each time rt_sigtimedwait_time32 system call is executed.





This function is hooked to record some information related to the signals and their structure when it is used in conjunctiob with the rt_sigtimedwait_time32 system call.

Example Use Case

The rt_sigtimedwait_time32 system call can be used to wait on synchronous signals arrivals with a given timeout, which is useful in workflows and systems which depend on real-time performance.


rt_sigtimedwait_time32 is susceptible to TOCTOU (time of check, time of use), because between the check and the actual use of the signal, the signal might change.

  • rt_sigtimedwait
  • rt_sigprocmask

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.