Struct ResolvOptions

pub struct ResolvOptions {

    pub search: SearchList,
    pub ndots: usize,
    pub timeout: Duration,
    pub attempts: usize,
    pub aa_only: bool,
    pub use_vc: bool,
    pub primary: bool,
    pub recurse: bool,
    pub default_names: bool,
    pub stay_open: bool,
    pub dn_search: bool,
    pub use_inet6: bool,
    pub rotate: bool,
    pub no_check_name: bool,
    pub keep_tsig: bool,
    pub blast: bool,
    pub use_bstring: bool,
    pub use_ip6dotint: bool,
    pub use_edns0: bool,
    pub single_request: bool,
    pub single_request_reopen: bool,
    pub no_tld_query: bool,
}

Options for the resolver configuration.

This type contains a lot of options that influence the resolver configuration. It collects all server-indpendent options that glibc’s resolver supports. Not all of them are currently supported by this implementation.

Fields

search: SearchList

Search list for host-name lookup.

ndots: usize

Number of dots before an initial absolute query is made.

timeout: Duration

Timeout to wait for a response.

attempts: usize

Number of retries before giving up.

aa_only: bool

Accept authoritative answers only.

Only responses with the AA bit set will be considered. If there aren’t any, the query will fail.

This option is not currently implemented. It is likely to be eventually implemented by the query.

use_vc: bool

Always use TCP.

This option is implemented by the query.

primary: bool

Query primary name servers only.

This option is not currently implemented. It is unclear what exactly it is supposed to mean.

recurse: bool

Set the recursion desired bit in queries.

Enabled by default.

Implemented by the query request.

default_names: bool

Append the default domain name to single component names.

Enabled by default.

This is not currently implemented. Instead, the resolver config’s search and ndots fields govern resolution of relative names of all kinds.

stay_open: bool

Keep TCP connections open between queries.

This is not currently implemented.

dn_search: bool

Search hostnames in the current domain and parent domains.

Enabled by default.

This options is not currently implemented. Instead, the resolver config’s search and ndots fields govern resolution of relative names.

use_inet6: bool

Try AAAA query before A query and map IPv4 responses to tunnel form.

This option is not currently implemented. It is only relevant for lookup_host.

rotate: bool

Use round-robin selection of name servers.

This option is implemented by the query.

no_check_name: bool

Disable checking of incoming hostname and mail names.

This is not currently implemented. Or rather, this is currently always on—there is no name checking as yet.

keep_tsig: bool

Do not strip TSIG records.

This is not currently implemented. Or rather, no records are stripped at all.

blast: bool

Send each query simultaneously to all name servers.

This is not currently implemented. It would be a query option.

use_bstring: bool

Use bit-label format for IPv6 reverse lookups.

Bit labels have been deprecated and consequently, this option is not implemented.

use_ip6dotint: bool

Use ip6.int instead of the recommended ip6.arpa.

(This option is the reverse of glibc’s RES_NOIP6DOTINT option).

This option is only relevant for lookup_addr() and is implemented there already.

use_edns0: bool

Use EDNS0.

EDNS is not yet supported.

single_request: bool

Perform IPv4 and IPv6 lookups sequentially instead of in parallel.

This is not yet implemented but would be an option for lookup_host().

single_request_reopen: bool

Open a new socket for each request.

This is not currently implemented.

no_tld_query: bool

Don’t look up unqualified names as top-level-domain.

This is not currently implemented. Instead, the resolver config’s search and ndots fields govern resolution of relative names of all kinds.

Trait Implementations

impl Clone for ResolvOptions

fn clone(&self) -> ResolvOptions

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ResolvOptions

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

Formats the value using the given formatter.

impl Default for ResolvOptions

fn default() -> Self

Returns the “default value” for a type.