go-delve/delve · error

you must provide a PID

Error message

you must provide a PID

What it means

Error "you must provide a PID" thrown in go-delve/delve.

Source

Thrown at cmd/dlv/cmds/commands.go:183

	must(rootCommand.RegisterFlagCompletionFunc("backend", cobra.FixedCompletions([]string{"default", "native", "lldb", "rr"}, cobra.ShellCompDirectiveNoFileComp)))
	rootCommand.PersistentFlags().StringArrayVarP(&redirects, "redirect", "r", []string{}, "Specifies redirect rules for target process (see 'dlv help redirect')")
	must(rootCommand.MarkPersistentFlagFilename("redirect"))
	rootCommand.PersistentFlags().BoolVar(&allowNonTerminalInteractive, "allow-non-terminal-interactive", false, "Allows interactive sessions of Delve that don't have a terminal as stdin, stdout and stderr")
	rootCommand.PersistentFlags().BoolVar(&disableASLR, "disable-aslr", false, "Disables address space randomization")

	// 'attach' subcommand.
	attachCommand := &cobra.Command{
		Use:   "attach pid [executable]",
		Short: "Attach to running process and begin debugging.",
		Long: `Attach to an already running process and begin debugging it.

This command will cause Delve to take control of an already running process, and
begin a new debug session.  When exiting the debug session you will have the
option to let the process continue or kill it.
`,
		PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
			if len(args) == 0 && attachWaitFor == "" {
				return errors.New("you must provide a PID")
			}
			return nil
		},
		Run: attachCmd,
		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
			if len(args) != 1 {
				return nil, cobra.ShellCompDirectiveNoFileComp
			}
			return nil, cobra.ShellCompDirectiveDefault
		},
	}
	attachCommand.Flags().BoolVar(&continueOnStart, "continue", false, "Continue the debugged process on start.")
	attachCommand.Flags().StringVar(&attachWaitFor, "waitfor", "", "Wait for a process with a name beginning with this prefix")
	must(attachCommand.RegisterFlagCompletionFunc("waitfor", cobra.NoFileCompletions))
	attachCommand.Flags().Float64Var(&attachWaitForInterval, "waitfor-interval", 1, "Interval between checks of the process list, in millisecond")
	must(attachCommand.RegisterFlagCompletionFunc("waitfor-interval", cobra.NoFileCompletions))
	attachCommand.Flags().Float64Var(&attachWaitForDuration, "waitfor-duration", 0, "Total time to wait for a process")
	must(attachCommand.RegisterFlagCompletionFunc("waitfor-duration", cobra.NoFileCompletions))

View on GitHub (pinned to a23773e6c3)

When it happens

Trigger: Thrown at cmd/dlv/cmds/commands.go:183 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of go-delve/delve@a23773e6c3 (2026-08-31). Data as JSON: /api/errors/d2ee445434910628. Report an issue: GitHub.