Not all os/error's handled in syscall.Errno.Is #37627
Description
What version of Go are you using (go version)?
$ go version go version go1.13.4 linux/amd64
Does this issue reproduce with the latest release?
Yes, there no changes.
What operating system and processor architecture are you using (go env)?
go env Output
$ go env GO111MODULE="" GOARCH="amd64" GOBIN="" GOCACHE="/home/user1/.cache/go-build" GOENV="/home/user1/.config/go/env" GOEXE="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="linux" GONOPROXY="" GONOSUMDB="" GOOS="linux" GOPATH="/home/user1/go" GOPRIVATE="" GOPROXY="https://proxy.golang.org,direct" GOROOT="/usr/lib/go-1.13" GOSUMDB="sum.golang.org" GOTMPDIR="" GOTOOLDIR="/usr/lib/go-1.13/pkg/tool/linux_amd64" GCCGO="gccgo" AR="ar" CC="gcc" CXX="g++" CGO_ENABLED="1" GOMOD="" CGO_CFLAGS="-g -O2" CGO_CPPFLAGS="" CGO_CXXFLAGS="-g -O2" CGO_FFLAGS="-g -O2" CGO_LDFLAGS="-g -O2" PKG_CONFIG="pkg-config" GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build325102545=/tmp/go-build -gno-record-gcc-switches"
What did you do?
Recommendation from https://golang.org/src/syscall/syscall_unix.go?s=2815:2833#L115 , use errors.Is, while checking error from syscall. But some os.Err*, not handled in syscall.Errno.Is. In the example I try to check for os.ErrInvalid, and always get false. I think it's little obscure, all errors defined in os/errors.go need be check.
package main
import (
"syscall"
"net"
"log"
"errors"
"os"
)
const TCP_FASTOPEN_CONNECT = 30
func main() {
addr, err := net.ResolveTCPAddr("tcp", "127.0.0.1:1337")
if err != nil {
log.Fatal(err)
}
li, err := net.ListenTCP("tcp", addr)
if err != nil {
log.Fatal(err)
}
conn, err := li.SyscallConn()
if err != nil {
log.Fatal(err)
}
conn.Control(func(fd uintptr) {
err = syscall.SetsockoptInt(int(fd), syscall.SOL_TCP, TCP_FASTOPEN_CONNECT, 5)
if errors.Is(err, os.ErrInvalid) {
log.Fatal("true ", err)
} else {
log.Fatal("false ", err) // false "invalid argument", the same as os.ErrInvalid
}
})
}What did you expect to see?
Actual check with:
if errors.Is(err, os.ErrInvalid) {
}
What did you see instead?
Always false.