Closed
Description
What version of Go are you using (go version)?
$ go version go version go1.13.4 darwin/amd64
Does this issue reproduce with the latest release?
This is the latest.
What operating system and processor architecture are you using (go env)?
go env Output
$ go env GO111MODULE="" GOARCH="amd64" GOBIN="" GOCACHE="/Users/cbarkerj/Library/Caches/go-build" GOENV="/Users/cbarkerj/Library/Application Support/go/env" GOEXE="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="darwin" GONOPROXY="" GONOSUMDB="" GOOS="darwin" GOPATH="/Users/cbarkerj/go" GOPRIVATE="" GOPROXY="https://proxy.golang.org,direct" GOROOT="/usr/local/go" GOSUMDB="sum.golang.org" GOTMPDIR="" GOTOOLDIR="/usr/local/go/pkg/tool/darwin_amd64" GCCGO="gccgo" AR="ar" CC="clang" CXX="clang++" 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 -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/9_/kzjd637s5n153w9g3zqc1hmh0000gn/T/go-build108700530=/tmp/go-build -gno-record-gcc-switches -fno-common"
What did you do?
This piece of code opens a directory file and calls f.Readdirnames(0). Then it calls f.Seek(0, 0) to reset to the head of the file, and calls f.Readdirnames(0) again.
https://play.golang.org/p/IEb3BH2Jlxg
What did you expect to see?
On Linux, the playground, and earlier versions of MacOS, the second call to f.Readdirnames(0) returns the same directory list as the first call:
$ go build .
$ ./test
2019/11/21 16:56:37 try 1:[test main.go]
2019/11/21 16:56:37 seeked to offset: 0
2019/11/21 16:56:37 try 2:[test main.go]
What did you see instead?
On MacOS 10.15.1 Catalina, the second call returns an empty list:
% go build .
% ./test
2019/11/21 16:55:22 try 1:[test main.go]
2019/11/21 16:55:22 seeked to offset: 0
2019/11/21 16:55:22 try 2:[]