# [−][src]Enum nix::sys::socket::ControlMessage

    pub enum ControlMessage<'a> {
        ScmRights(&'a [RawFd]),
        ScmCredentials(&'a ucred),
        AlgSetIv(&'a [u8]),
        AlgSetOp(&'a c_int),
        AlgSetAeadAssoclen(&'a u32),
    }

A type-safe zero-copy wrapper around a single control message, as used wih `sendmsg`. More types may be added to this enum; do not exhaustively pattern-match it.

Further reading

## Variants

`ScmRights(&'a [RawFd])`

A message of type `SCM_RIGHTS`, containing an array of file descriptors passed between processes.

See the description in the "Ancillary messages" section of the unix(7) man page.

Using multiple `ScmRights` messages for a single `sendmsg` call isn't recommended since it causes platform-dependent behaviour: It might swallow all but the first `ScmRights` message or fail with `EINVAL`. Instead, you can put all fds to be passed into a single `ScmRights` message.

`ScmCredentials(&'a ucred)`

A message of type `SCM_CREDENTIALS`, containing the pid, uid and gid of a process connected to the socket.

This is similar to the socket option `SO_PEERCRED`, but requires a process to explicitly send its credentials. A process running as root is allowed to specify any credentials, while credentials sent by other processes are verified by the kernel.

For further information, please refer to the `unix(7)` man page.

`AlgSetIv(&'a [u8])`

Set IV for `AF_ALG` crypto API.

For further information, please refer to the `documentation`

`AlgSetOp(&'a c_int)`

Set crypto operation for `AF_ALG` crypto API. It may be one of `ALG_OP_ENCRYPT` or `ALG_OP_DECRYPT`

For further information, please refer to the `documentation`

`AlgSetAeadAssoclen(&'a u32)`

Set the length of associated authentication data (AAD) (applicable only to AEAD algorithms) for `AF_ALG` crypto API.

For further information, please refer to the `documentation`

## Auto Trait Implementations

### `impl<'a> Send for ControlMessage<'a>`

### `impl<'a> Unpin for ControlMessage<'a>`

### `impl<'a> Sync for ControlMessage<'a>`

### `impl<'a> UnwindSafe for ControlMessage<'a>`

### `impl<'a> RefUnwindSafe for ControlMessage<'a>`

## Blanket Implementations

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `fn into(self) -> U`[src]

Performs the conversion.

### `impl<T> From<T> for T`[src]

#### `fn from(t: T) -> T`[src]

Performs the conversion.

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

#### `type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

#### `fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `fn borrow_mut(&mut self) -> &mut T`[src]

Mutably borrows from an owned value. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `fn borrow(&self) -> &T`[src]

Immutably borrows from an owned value. Read more

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

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