Function TerminateModuleForkChild

app/redis-6.2.6/src/module.c:7898–7915

Kill the active module forked child, if there is one active and the * pid matches, and returns C_OK. Otherwise if there is no active module * child or the pid does not match, return C_ERR without doing anything. */

 * pid matches, and returns C_OK. Otherwise if there is no active module
 * child or the pid does not match, return C_ERR without doing anything. */
int TerminateModuleForkChild(int child_pid, int wait) {
    /* Module child should be active and pid should match. */
    if (server.child_type != CHILD_TYPE_MODULE ||
        server.child_pid != child_pid) return C_ERR;

    int statloc;
    serverLog(LL_VERBOSE,"Killing running module fork child: %ld",
        (long) server.child_pid);
    if (kill(server.child_pid,SIGUSR1) != -1 && wait) {
        while(waitpid(server.child_pid, &statloc, 0) !=
              server.child_pid);
    }
    /* Reset the buffer accumulating changes while the child saves. */
    resetChildState();
    moduleForkInfo.done_handler = NULL;
    moduleForkInfo.done_handler_user_data = NULL;
    return C_OK;
}

/* Can be used to kill the forked child process from the parent process.
 * child_pid would be the return value of RedisModule_Fork. */