Struct Flags 

pub struct Flags {
    pub broadcast: bool,
}

Wraps a bit field used in Message.

The two bytes that this field occupies were unused in RFC-951, and later defined then clarified in RFC-1542.

The leftmost bit is defined as the Broadcast flag. The remaining bits are reserved for future use, and must be set to zero by clients and ignored by servers and relay agents.

Fields

broadcast: bool

Used to work around some clients that cannot accept IP unicast datagrams before the TCP/IP software is configured.

Implementations

impl Flags

pub const fn temporary_to_bytes(&self) -> [u8; 2]

As long as the flags field is only used for broadcasts then this method can be used as a faster way to serialize the broadcast value to bytes.

Otherwise, you’ll want to use the existing From impl.

As of 2025 I do not see any RFC that updates RFC-2131 with new flags.

Trait Implementations

impl Debug for Flags

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<&Flags> for [u8; 2]

fn from(flags: &Flags) -> Self

Converts to this type from the input type.

impl From<u8> for Flags

Converts the only byte currently used by the flags field. For use with UndecodedMessage’s slice_flags_temporary.

Warning: If more bit flags are added via RFC then this may need to change or be removed.

fn from(byte: u8) -> Self

Converts to this type from the input type.

impl PartialEq for Flags

fn eq(&self, other: &Flags) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Flags