msgexec

msgexec [-v] [-t ]

    The message queue ID (an integer) to listen on.

-v
    Verbose mode, prints the command being executed before execution.

-t
    Timeout in seconds to wait for a message. If omitted, msgexec will wait indefinitely.

The msgexec command is a utility for executing commands stored within a System V message queue.
It acts as a listener, continuously monitoring a specified message queue for messages containing executable commands.
When a message is received, msgexec retrieves the command from the message data and executes it using /bin/sh.
The command provides a simple mechanism for inter-process communication and allows one process to trigger the execution of commands in another, without direct function calls.
This can be used for asynchronous task execution or distributed processing within a system.
msgexec is often used in conjunction with message queue manipulation commands like msgget, msgsnd, and msgrcv, which are part of the System V inter-process communication (IPC) facility.
It is important to properly manage permissions and message queue keys to ensure secure communication and prevent unauthorized command execution.

msgexec executes commands using /bin/sh.
Therefore, commands passed to it should be carefully sanitized to prevent command injection vulnerabilities.
Additionally, errors during command execution will not be directly reported back to the sender, making error handling more complex.

Executing arbitrary commands received from a message queue can pose significant security risks.
It is crucial to validate and sanitize all commands before execution to prevent malicious code from being injected.
Consider limiting the commands that can be executed to a predefined set, or using a more secure form of inter-process communication if security is a paramount concern.

msgexec does not provide built-in error handling for the executed commands.
If error reporting is required, consider wrapping the executed commands in a script that captures the output and error codes, then sends them back via another message queue or other communication channel.

msgexec is part of the util-linux package.
It provides a useful function related to systemv message queues which existed since early UNIX systems.
Its main objective is to create a easy command which executes commands from message queues.
Over the time, alternative approaches like sockets are often prefered but it still could be used.

msgget(1), msgsnd(1), msgrcv(1), ipcrm(1)