[#Lookup-0d]
= Lookup
:mrdocs:

`Lookup` overloads

== Synopses

Declared in `<netbase.h>`

Resolve a service string to its first corresponding service.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
std::optional<CService>
xref:Lookup-0b.adoc[Lookup](
    std::string const& name,
    uint16_t portDefault,
    bool fAllowLookup,
    xref:DNSLookupFn.adoc[DNSLookupFn] dns_lookup_function = g_dns_lookup);
----

[.small]#xref:Lookup-0b.adoc[_» more..._]#

Resolve a service string to its corresponding service.


[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
std::vector<CService>
xref:Lookup-04.adoc[Lookup](
    std::string const& name,
    uint16_t portDefault,
    bool fAllowLookup,
    unsigned int nMaxSolutions,
    xref:DNSLookupFn.adoc[DNSLookupFn] dns_lookup_function = g_dns_lookup);
----

[.small]#xref:Lookup-04.adoc[_» more..._]#

== Return Value

* The first resolved service, or std::nullopt if the string does not resolve.
* The resulting services to which the specified service string resolved.

== Parameters

[cols="1,4"]
|===
| Name| Description
| *name*
| The service string to resolve.
| *portDefault*
| The port to use when the service string omits one.
| *fAllowLookup*
| Whether DNS lookups are permitted.
| *dns_lookup_function*
| The resolver used to perform the lookup.
| *nMaxSolutions*
| The maximum number of results we want, specifying 0 means "as many solutions as we get."
|===

== See Also

Lookup(const std::string&, uint16_t, bool, unsigned int, DNSLookupFn) for additional parameter descriptions.


[.small]#Created with https://www.mrdocs.com[MrDocs]#