sigreturn¶

Intro¶

sigreturn - restore process state after receiving a signal

Description¶

The sigreturn() system call restores the calling process' pre-signal state, and is usually used when the user wants to implement their own signal handlers. This can be done by setting the SA_SIGINFO flag when registering the signal handler, and then calling sigreturn() in order to restore the process state. One of the main advantages of using sigreturn() is that it is significantly faster than sigaction().

However, there are some drawbacks to using this system call. Most notably, any change that is made to the process state after calling sigreturn(), before the process is switched from the kernel to user space again, will be lost. This includes changes to any data structures, resources, or file descriptors, as well as any additional system calls that might be made.

Arguments¶

This system call takes no arguments.

Hooks¶

do_signal¶

Type¶

kprobes

Purpose¶

This function is hooked in order to catch the sigreturn() system call and perform any necessary cleanup tasks.

Example Use Case¶

One use case for sigreturn() might be a signal handler that can be used to safely shut down a process. Since sigreturn() restores the process's state to its state before the signal, it can be used in order to safely shut down the process without causing any errors or data inconsistencies.

Issues¶

There are no known issues with the sigreturn() system call.

sigaction() - register a signal handler
sigprocmask() - manipulate a process's signal mask

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.