1Socket::GetAddrInfo::EmUusle(r3)Contributed Perl DocumenStoactkieotn::GetAddrInfo::Emul(3)
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NAME

6       "Socket::GetAddrInfo::Emul" - Pure Perl emulation of "getaddrinfo" and
7       "getnameinfo" using IPv4-only legacy resolvers
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DESCRIPTION

10       "Socket::GetAddrInfo" attempts to provide the "getaddrinfo" and
11       "getnameinfo" functions by some XS code that calls the real functions
12       in libc. If for some reason this cannot be done; either there is no C
13       compiler, or libc does not provide these functions, then they will be
14       emulated using the legacy resolvers "gethostbyname", etc... These
15       emulations are not a complete replacement of the real functions,
16       because they only support IPv4 (the "AF_INET" socket family). In this
17       case, the following restrictions will apply.
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19   getaddrinfo
20       ·   If the "family" hint is supplied, it must be "AF_INET". Any other
21           value will result in an error thrown by "croak".
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23       ·   The only supported "flags" hint values are "AI_PASSIVE",
24           "AI_CANONNAME", "AI_NUMERICSERV" and "AI_NUMERICHOST".
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26           The flags "AI_V4MAPPED" and "AI_ALL" are recognised but ignored, as
27           they do not apply to "AF_INET" lookups.  Since this function only
28           returns "AF_INET" addresses, it does not need to probe the system
29           for configured addresses in other families, so the "AI_ADDRCONFIG"
30           flag is also ignored.
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32           Note that "AI_NUMERICSERV" is an extension not defined by RFC 2553,
33           but is provided by most OSes. It is possible (though unlikely) that
34           even the native XS implementation does not recognise this constant.
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36   getnameinfo
37       ·   If the sockaddr family of $addr is anything other than "AF_INET",
38           an error will be thrown with "croak".
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40       ·   The only supported $flags values are "NI_NUMERICHOST",
41           "NI_NUMERICSERV", "NI_NOFQDN", "NI_NAMEREQD" and "NI_DGRAM".
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IDN SUPPORT

44       This pure-perl emulation provides the IDN constants such as "AI_IDN"
45       and "NI_IDN", but the "getaddrinfo" and "getnameinfo" functions will
46       croak if passed these flags. This should allow a program to probe for
47       their support, and fall back to some other behaviour instead.
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AUTHOR

50       Paul Evans <leonerd@leonerd.org.uk>
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54perl v5.32.0                      2020-07-28      Socket::GetAddrInfo::Emul(3)