Sockets: fix getipaddr/getipaddrs documentation, add islinklocaladdr function #34300
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- resolved IPv4/IPv6 confusion, e.g. getipaddrs() does _not_ return only IPv4 - more realistic example addresses - example addresses taken from address ranges reserved for documentation https://en.wikipedia.org/wiki/Reserved_IP_addresses
Keno
reviewed
Jan 7, 2020
stdlib/Sockets/src/addrinfo.jl
Outdated
| """ | ||
| function islinklocaladdr(addr::IPv4) | ||
| # RFC 3927 | ||
| return addr.host & |
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This could use parens around the & I think. Looks odd otherwise.
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OK, parentheses now added in rebased commit b62e10c.
IPv6 interfaces always have a link-local address configured, which is also reported by getipaddrs(). However, typical application servers are not reachable under their link-local address, therefore this convenience function helps users of getipaddrs() to filter out such addresses with `filter(!islinklocaladdr, getipaddrs())`. This commits also adds a "See also" hint that in applications where a server process has been started remotely via ssh that `split(ENV["SSH_CONNECTION"], ' ')[3]` can be a preferable alternative source for the IP address under which this server is reachable (namely the address that ssh has already used successfully to get here).
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@Keno Ready to be merged? (the buildbot/tester_win32 failure seems unrelated to this PR and I don't have permission to press the Rebuild button on https://build.julialang.org/#/builders/65/builds/6777: "Cannot rebuild: you need to have role 'JuliaLang'", how does one get this?) |
JeffBezanson
approved these changes
Jan 13, 2020
KristofferC
pushed a commit
that referenced
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Apr 11, 2020
…function (#34300) * fix getipaddr/getipaddrs documentation - resolved IPv4/IPv6 confusion, e.g. getipaddrs() does _not_ return only IPv4 - more realistic example addresses - example addresses taken from address ranges reserved for documentation https://en.wikipedia.org/wiki/Reserved_IP_addresses * add Sockets.islinklocaladdr IPv6 interfaces always have a link-local address configured, which is also reported by getipaddrs(). However, typical application servers are not reachable under their link-local address, therefore this convenience function helps users of getipaddrs() to filter out such addresses with `filter(!islinklocaladdr, getipaddrs())`. This commits also adds a "See also" hint that in applications where a server process has been started remotely via ssh that `split(ENV["SSH_CONNECTION"], ' ')[3]` can be a preferable alternative source for the IP address under which this server is reachable (namely the address that ssh has already used successfully to get here).
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Fix
getipaddr/getipaddrsdocumentation:resolved IPv4/IPv6 confusion, e.g.
getipaddrs()does not return only IPv4more realistic example addresses (not just non-routeable IPv6 link-local addresses)
example addresses taken from address ranges reserved for documentation https://en.wikipedia.org/wiki/Reserved_IP_addresses
Add
Sockets.islinklocaladdr:IPv6 interfaces always have an fe80::/10 link-local address configured, which is also reported by getipaddrs(). However, typical application servers are not reachable under their link-local address, therefore this convenience function helps users of getipaddrs() to filter out such addresses with
filter(!islinklocaladdr, getipaddrs()).This commit also adds a "See also" hint to make potential users of
getaddrsaware that in applications where a server process has been started remotely via ssh the address found insplit(ENV["SSH_CONNECTION"], ' ')[3]can be a preferable alternative source for an IP address under which this server is reachable, namely the very IP address that ssh has already used successfully to get here.