The interface is defined in a file in syscall that exists on all platforms: https://golang.org/src/syscall/net.go?s=219:984#L1.
Any operations you'd want to perform with it would probably invoke OS-specific APIs, but the same rule applies to using the file descriptor directly after invoking File. So my question still stands, as far as I know. On Monday, March 25, 2019 at 2:36:29 PM UTC-4, Robert Engels wrote: > > File is cross-platform. I am pretty sure no syscall.XXXX is guaranteed to > be available on any given platform. > > -----Original Message----- > From: Matt Layher > Sent: Mar 25, 2019 1:03 PM > To: golang-nuts > Subject: [go-nuts] net.Conn types: File vs SyscallConn method > > I've been doing low-level networking work in Go for a few years now, but I > had a realization the other day: > > With the addition of the SyscallConn method in Go 1.9 to several > net.Conn/PacketConn types, what is the advantage of using the File method > at this point in time? > > The documentation (https://golang.org/pkg/net/#IPConn.File) mentions: > > > File returns a copy of the underlying os.File It is the caller's > responsibility to close f when finished. Closing c does not affect f, and > closing f does not affect c. > > > > The returned os.File's file descriptor is different from the > connection's. Attempting to change properties of the original using this > duplicate may or may not have the desired effect. > > But the syscall.RawConn provides a handle to a non-dup'd file descriptor, > which can be used for dealing with socket options and runtime network > poller-integrated reads/writes. To my knowledge, changing the properties of > the file descriptor passed in syscall.RawConn methods will always have the > desired effect, because it offers direct access to the file descriptor. > > Which leads to my next question: if SyscallConn provides better > flexibility, is it time to add a deprecation notice to the File method on > various package net types, in favor of SyscallConn? > > Perhaps there's some benefit to File that I'm not seeing. If so, I'd be > curious to find out! > > Thanks, > Matt Layher (@mdlayher) > > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts...@googlegroups.com <javascript:>. > For more options, visit https://groups.google.com/d/optout. > > > > > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
