Function detectVersion

internal/tools/installer.go:193–221

detectVersion probes the binary with a sequence of version flags, returning the first non-empty response. Each probe is bounded: the process is killed after versionProbeTimeout, and its pipes are forcibly closed after versionProbeWaitDelay so a hung grandchild can't deadlock the read. If a flag time

(bin string)

// times out, the remaining flags are skipped — a binary that hangs on one
// version flag will hang on the others too.
func detectVersion(bin string) string {
	for _, flag := range []string{"--version", "-v", "version"} {
		ctx, cancel := context.WithTimeout(context.Background(), versionProbeTimeout)
		cmd := exec.CommandContext(ctx, bin, flag)
		cmd.WaitDelay = versionProbeWaitDelay
		out, err := cmd.CombinedOutput()
		timedOut := ctx.Err() != nil // deadline fired (cancel runs below)
		cancel()
		if err != nil {
			if timedOut {
				break
			}
			continue
		}
		s := strings.TrimSpace(string(out))
		if s == "" {
			continue
		}
		// Take the last non-empty line.
		lines := strings.Split(s, "\n")
		for i := len(lines) - 1; i >= 0; i-- {
			line := strings.TrimSpace(lines[i])
			if line != "" {
				return line
			}
		}
	}
	return "unknown"
}