go-delve/delve · error

procstat_getprocs failed: %v

Error message

procstat_getprocs failed: %v

What it means

Inside EntryPoint on FreeBSD, procstat_getprocs(ps, KERN_PROC_PID, pid, &count) failed to fetch the process's kinfo_proc entries for the debugged pid. Delve needs this record before querying the auxiliary vector, so it aborts with this error.

Source

Thrown at pkg/proc/native/proc_freebsd.go:593

		for _, th := range dbp.threads {
			ptraceResume(th.ID)
		}
	}
	return ptraceDetach(dbp.pid)
}

// EntryPoint returns the entry point address of the process.
func (dbp *nativeProcess) EntryPoint() (uint64, error) {
	ps, err := C.procstat_open_sysctl()
	if err != nil {
		return 0, fmt.Errorf("procstat_open_sysctl failed: %v", err)
	}
	defer C.procstat_close(ps)

	var count C.uint
	kipp, err := C.procstat_getprocs(ps, C.KERN_PROC_PID, C.int(dbp.pid), &count)
	if err != nil {
		return 0, fmt.Errorf("procstat_getprocs failed: %v", err)
	}
	defer C.procstat_freeprocs(ps, kipp)
	if count == 0 {
		return 0, errors.New("procstat_getprocs returned no processes")
	}

	auxv, err := C.procstat_getauxv(ps, kipp, &count)
	if err != nil {
		return 0, fmt.Errorf("procstat_getauxv failed: %v", err)
	}
	defer C.procstat_freeauxv(ps, auxv)

	for i := 0; i < int(count); i++ {
		if auxv.a_type == C.AT_ENTRY {
			return uint64(C.elf_aux_info_ptr(auxv)), nil
		}
		auxv = (*C.Elf_Auxinfo)(unsafe.Pointer(uintptr(unsafe.Pointer(auxv)) + unsafe.Sizeof(*auxv)))
	}

View on GitHub (pinned to a23773e6c3)

Solutions

1. Confirm the target is still alive (ps -p <pid>) before calling APIs that need process metadata.
2. Re-run delve as root or the same user as the target if visibility is the issue.
3. Retry quickly: if this was a race with process exit, catch ErrProcessExited-style conditions and handle the dead target.
4. Update FreeBSD/libprocstat if getprocs fails for a valid, visible pid.

Example fix

// before
ep, err := proc.EntryPoint() // procstat_getprocs failed: no such process

// after
if proc.Exited() {
    return // target already gone, skip entry-point lookup
}
ep, err := proc.EntryPoint()

// check target liveness and visibility before EntryPoint
func pidVisible(pid int) bool {
    return exec.Command("procstat", strconv.Itoa(pid)).Run() == nil
}

if !pidVisible(pid) { return ErrTargetGone }
ep, err := proc.EntryPoint()
if err != nil && strings.Contains(err.Error(), "procstat_getprocs failed") {
    return fmt.Errorf("target %d exited during entry-point lookup", pid)
}

When it happens

Trigger: procstat_getprocs returns non-zero when EntryPoint runs — the pid does not exist anymore, is not visible to the calling user, or the procstat handle is invalid.

Common situations: Target exited before EntryPoint was called (race with process death); running in a jail or as an unprivileged user who cannot see the target's process record; pid reuse confusion in scripts that parse the error.

Related errors

• procstat_open_sysctl failed: %v
• procstat_getauxv failed: %v
• procstat_getprocs returned no processes
• kinfo_getvmmap call failed
• entry point not found

AI-assisted analysis of go-delve/delve@a23773e6c3 (2026-08-31). Data as JSON: /api/errors/75108ca68d224da0. Report an issue: GitHub.