Programmatically, what does the kernel actually do with data sent to /dev/null?

I imagine it’s like getting nullified in that olde show ReBoot.

The syscall to write passes a buffer and length. If it is Dev null the call just returns without doing anything more.

I was also curious, here’s a good answer:

https://unix.stackexchange.com/questions/670199/how-is-dev-null-implemented

The implementation is:

static ssize_t write_null(struct file *file, const char __user *buf,
              size_t count, loff_t *ppos)
{
    return count;
}