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semop

Intro

semop - atomically perform operations on a set of semaphores

Description

Semop is a Linux system call used to perform operations on a set of semaphores. It ensures that all operations specified in the argument sops will either be completed or none of them will be performed at all. This call can be used for synchronization between threads or processes. The only drawback is that if the maximum number of semaphores allowed is reached, the call will fail.

Arguments

  • semid:int - ID of the set of semaphores.
  • sops:struct sembuf* - pointer to an array of semaphore operations.
  • nsops:size_t - number of semaphores in the array.

Available Tags

  • KU - Originated from kernel-space or user space.
  • OPT - Optional argument - might not always be available (passed with null value)

Hooks

sys_semop

Type

kprobe

Purpose

To gain insight to the arguments passed to semop, as well as to log any broken semaphore constraints.

Example Use Case

If you need to synchronize between threads or processes, semop can be used to guarantee that a set of operations on a set of semaphores will either all succeed or none of them will.

Issues

If the maximum number of semaphores allowed is reached, the call will fail.

  • semget - Gets an existing semaphore set or allocate a new one.
  • semctl - Examine or change an existing semaphore set.
  • semtimedop - Like semop, but with an additional timeout parameter.

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.