os.exec and file path resolving

[mwriter]

Go version

1.24.3

Output of go env in your module/workspace:

AR='ar'
CC='gcc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='g++'
GCCGO='gccgo'
GO111MODULE=''
GOAMD64='v1'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/home/mwriter/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/home/mwriter/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build589407262=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/home/mwriter/go/test/go.mod'
GOMODCACHE='/home/mwriter/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/home/mwriter/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/home/mwriter/bin/go'
GOSUMDB='sum.golang.org'
GOTELEMETRY='on'
GOTELEMETRYDIR='/home/mwriter/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/home/mwriter/bin/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.24.3'
GOWORK=''
PKG_CONFIG='pkg-config'

What did you do?

I don't know how such a bug could have gone unnoticed for years, but it still exists.

It's working

import (
	"os"
	"os/exec"
)

func main() {
	p := "some_path"
	os.Setenv("PATH", p);
	cmd := exec.Command("some_binary_name")
	err := cmd.Start() // <nil>
}

But

import (
	"os"
	"os/exec"
)

func main() {
	p := "some_path"
	cmd := exec.Command("some_binary_name")
	os.Setenv("PATH", p);
	err := cmd.Start() // exec: "some_binary_name": executable file not found in $PATH
}

import (
	"fmt"
	"os/exec"
)

func main() {
	p := "some_path"
	cmd := exec.Command("some_binary_name")
	cmd.Env = append([]string{}, fmt.Sprintf("PATH=%v", p))
	err := cmd.Start() // exec: "some_binary_name": executable file not found in $PATH
}

What did you see happen?

I see a big problem in resolving file paths.

What did you expect to see?

Need to change the resolving of file paths not at the time of creation of exec command object, but at the time of its launch. And rewrite it so that the field cmd.Env is also used.

[gabyhelp]

Related Issues

• os/exec: cmd.Env doesn't use provided PATH #53996 (closed)
• `os.Executable` path resolution broken if path contains space #67946 (closed)
• os/exec: LookPath() doesn't consider chroot #39341
• cmd/go: `go build` (etc.) doesn't work with symlinks when invoked via os/exec.Command with mismatched PWD #63644 (closed)
• os/exec: PATH in windows ErrNotFound is not escaped #38994 (closed)
• os/exec: look in current directory for executable on all platforms? #7570 (closed)
• os/exec: calling Cmd.Start after setting Cmd.Path manually to absolute path without ".exe" no longer implicitly adds ".exe" in Go 1.22 #66586 (closed)
• os/exec: unexpected ErrDot returned if there is an empty path in PATH #61493 (closed)
• os/exec: exec.LookPath return errors when PATH starts with semicolon (parsed as contains empty string at first) and working directory is same as the target executable on windows #69636 (closed)
• os/exec: Cmd does not attempt to run ./prog.exe, when execution of ./prog requested #7377 (closed)

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[seankhliao]

Closing as working as intended.

Unlike many projects, the Go project does not use GitHub Issues for general discussion or asking questions. GitHub Issues are used for tracking bugs and proposals only.

For questions please refer to https://github.com/golang/go/wiki/Questions

[mwriter]

Unlike many projects, the Go project does not use GitHub Issues for general discussion or asking questions. GitHub Issues are used for tracking bugs and proposals only.

This is an obvious bug, because itself command environment variables are not applied when path resolving.
In other languages, similar constructions work as expected.

[mwriter]

• os/exec: cmd.Env doesn't use provided PATH os/exec: cmd.Env doesn't use provided PATH #53996 (closed)

• os/exec: LookPath() doesn't consider chroot os/exec: LookPath() doesn't consider chroot #39341

Yes, it's the same bug.
As a result, it turned out to be easier to rewrite golang core code than to wait for your adequacy in solving bugs.