function::sa_handler - Linux

Overview

function::sa_handler helps register a signal handler function in a shared library. This enables the library to handle specific signals sent to the process that loaded it. It’s useful when creating reusable signal handling modules in the form of shared libraries.

Syntax

int function::sa_handler(const char *, void (*)(int), void *, void (*)(void), void *)

Parameters:

• const char *name: Name of the signal to handle.
• void (*handler)(int): Function pointer to the signal handler.
• void *arg: An optional argument to pass to the signal handler.
• void (*context_init)(void): An optional function to initialize the signal handler context.
• void *context: An optional context pointer to pass to the context_init function.

Options/Flags

None

Examples

Register a signal handler for the SIGTERM signal:

int sa_handler_success = function::sa_handler(
    "SIGTERM",  // Handle SIGTERM
    [](int signum) {
        // Signal handler code
    },
    nullptr,
    nullptr,
    nullptr);

Common Issues

• Ensure the signal handler function has the correct signature (void (*)(int)).
• Check if the signal name is valid and recognized by the system.
• Use sigaction(2) directly if you need more control over the signal handling behavior.

Integration

function::sa_handler can be used in conjunction with other library functions to build advanced signal handling modules. For example, a library can expose a registration API that allows users to subscribe to specific signals and provide their own handlers.

Related Commands

• sigaction(2): Sets the signal handling behavior.
• signal(2): Sets the signal handling behavior (less flexible than sigaction).