tsenart/vegeta · error

error opening

Error message

error opening %s: %s

What it means

attack() opens the targets file and optional body file before launching the attack; if `file()` (os.Open-style) fails, the error is wrapped with the offending filename. This almost always means the path does not exist or is not readable.

Solutions

1. Verify the file exists at the given path (`ls <path>`) and fix the path/typo.
2. Run vegeta from the directory you expect, or use absolute paths for -targets/-body.
3. Check file permissions (readable by the user running vegeta); if the path is a directory, point to a regular file.

Example fix

// before
vegeta attack -targets=./tragets.txt
// after
vegeta attack -targets=./targets.txt

for _, f := range []string{targetsPath, bodyPath} {
    if f == "" { continue }
    if st, err := os.Stat(f); err != nil || st.IsDir() {
        return fmt.Errorf("input %q is not a readable file", f)
    }
}

When it happens

Trigger: Passing `-targets=<path>` or `-body=<path>` pointing to a nonexistent file, a directory, or a file the current user cannot read.

Common situations: Typo in path; running vegeta from a different working directory than assumed; relative path in cron/CI with different cwd; missing permissions in containerized environments.

Understand the failure class

Background: "File not found" and ENOENT errors: why libraries can't find a file that should exist — this error's family across 50 libraries.

Related errors

• error reading
• bad body
• bad buckets
• encode: can't detect encoding of
• encode: unknown encoding

AI-assisted analysis of tsenart/vegeta@cf58112690 (2026-08-31). Data as JSON: /api/errors/07e454588ff8cc8a. Report an issue: GitHub.

Appendix: source

Thrown at attack.go:139

	if len(opts.resolvers) > 0 {
		res, err := resolver.NewResolver(opts.resolvers)
		if err != nil {
			return err
		}
		net.DefaultResolver = res
	}

	net.DefaultResolver.PreferGo = true

	files := map[string]io.Reader{}
	for _, filename := range []string{opts.targetsf, opts.bodyf} {
		if filename == "" {
			continue
		}
		f, err := file(filename, false)
		if err != nil {
			return fmt.Errorf("error opening %s: %s", filename, err)
		}
		defer f.Close()
		files[filename] = f
	}

	var body []byte
	if bodyf, ok := files[opts.bodyf]; ok {
		if body, err = io.ReadAll(bodyf); err != nil {
			return fmt.Errorf("error reading %s: %s", opts.bodyf, err)
		}
	}

	var (
		tr       vegeta.Targeter
		src      = files[opts.targetsf]
		hdr      = opts.headers.Header
		proxyHdr = opts.proxyHeaders.Header
	)

View on GitHub (pinned to cf58112690)