os/exec to run shell cmd "rsh" bug

Question

$ go version

go version go1.18 windows/amd64

$ go env

set GO111MODULE=on
set GOARCH=amd64
set GOBIN=
set GOCACHE=C:\Users\Binglei.Hou\AppData\Local\go-build
set GOENV=C:\Users\Binglei.Hou\AppData\Roaming\go\env
set GOEXE=
set GOEXPERIMENT=
set GOFLAGS=
set GOHOSTARCH=amd64
set GOHOSTOS=windows
set GOINSECURE=
set GOMODCACHE=D:\gocode\pkg\mod
set GONOPROXY=*.corp.example.com
set GONOSUMDB=*.corp.example.com
set GOOS=linux
set GOPATH=D:\gocode
set GOPRIVATE=*.corp.example.com
set GOPROXY=https://goproxy.cn,direct
set GOROOT=D:\go
set GOSUMDB=sum.golang.org
set GOTMPDIR=
set GOTOOLDIR=D:\go\pkg\tool\windows_amd64
set GOVCS=
set GOVERSION=go1.18
set GCCGO=gccgo
set GOAMD64=v1
set AR=ar
set CC=gcc
set CXX=g++
set CGO_ENABLED=0
set GOMOD=D:\gocode\src\vg-monitor\go.mod
set GOWORK=
set CGO_CFLAGS=-g -O2
set CGO_CPPFLAGS=
set CGO_CXXFLAGS=-g -O2
set CGO_FFLAGS=-g -O2
set CGO_LDFLAGS=-g -O2
set PKG_CONFIG=pkg-config
set GOGCCFLAGS=-fPIC -m64 -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=C:\Users\Binglei.Hou\AppData\Local\Temp\go-build564106301=/tmp/go-build -gno-record-gcc-switches

What did you do?

I used exec.Command to run rsh cmd in for:

for _, value := range this.Info {
    cmd := exec.Command("rsh", "-l", "monitor", value[0], "sh", "tru", "grou")
    var stdout bytes.Buffer
    cmd.Stdout = &stdout
            err := cmd.Run()
    if err != nil {
        fmt.Println("cmd start err is:", err)
    }
    fmt.Println(value[0], "---> start")
    fmt.Println("stdout is :", stdout.String())

value[0] means remote host IP.

What did you expect to see?

i expect each result of stdout.Sting() has value

What did you see instead?

some stdout.Sting() has value, and some not. and remote host IP id different during every for func. for example one may be 1.1.1.1 has no result, and next time 1.1.1.1 may have result, but 2.2.2.2 may be has no value.