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API Reference
WASIX
proc_signal

proc_signal()

Sends a signal to a child process.

Description

The proc_signal() function is used to send a signal to a specific child process identified by its PID. The signal specified by the sig parameter is sent to the child process, which allows for various forms of inter-process communication and process control.

On POSIX systems, a similar functionality is provided by the kill() function. It allows sending a signal to a process or a group of processes identified by their process ID. The kill() function is part of the POSIX standard and is widely supported across different platforms.

Syntax

  ;;; Sends a signal to another process
  (@interface func (export "proc_signal")
    ;;; ID of the process to send a singal
    (param $pid $pid)
    ;;; Signal to send to the thread
    (param $signal $signal)
    (result $error (expected (error $errno)))
  )

Parameters

  • ctx: A mutable reference to the function environment.
  • pid: The PID of the child process to which the signal will be sent.
  • sig: The signal to send to the child process.

Return Value

The function returns a Result indicating the success or failure of the operation. If the operation is successful, it returns Ok(Errno::Success). Otherwise, it returns an appropriate WasiError value.

Logging

This function is instrumented with trace level logging. It includes the following fields for debugging purposes:

  • pid: The PID of the child process.
  • sig: The signal being sent.

Notes

  • The proc_signal() function sends a signal to the child process identified by its PID.
  • If a process with the specified PID is found, the signal specified by the sig parameter is sent to that process.
  • On POSIX systems, a similar functionality is provided by the kill() function, which allows sending signals to processes identified by their process ID.
  • Sending signals to processes enables inter-process communication and process control. Signals can be used for various purposes, such as terminating a process, handling specific events, or requesting actions from the receiving process.
proc_joinport_bridge