pub fn sys_clone(
    flags: u32,
    stack: *const u8,
    ptid: *const u32,
    tls: *const usize,
    ctid: *const u32
) -> isize
Expand description

Explanation of Parameters

Mainly about ptid, tls and ctid:
CLONE_SETTLS: The TLS (Thread Local Storage) descriptor is set to tls.
CLONE_PARENT_SETTID: Store the child thread ID at the location pointed to by ptid in the parent’s memory.
CLONE_CHILD_SETTID: Store the child thread ID at the location pointed to by ctid in the child’s memory.
ptid is also used in CLONE_PIDFD (since Linux 5.2)
Since user programs rarely use these, we could do lazy implementation.