wavetermdev/waveterm · error

procinfo: Process32Next: %w

Error message

procinfo: Process32Next: %w

What it means

During snapshot iteration, Process32Next advances to the next process entry; ERROR_NO_MORE_FILES is the expected clean end of iteration and breaks the loop, but any other error is wrapped in this error. It means iteration aborted mid-scan and the returned snapshot would be incomplete, so it is discarded.

Source

Thrown at pkg/util/procinfo/procinfo_windows.go:72

	var entry windows.ProcessEntry32
	entry.Size = uint32(unsafe.Sizeof(entry))

	if err := windows.Process32First(snap, &entry); err != nil {
		return nil, fmt.Errorf("procinfo: Process32First: %w", err)
	}
	for {
		pid := int32(entry.ProcessID)
		procs[pid] = &snapInfo{
			ppid:       entry.ParentProcessID,
			numThreads: entry.Threads,
			exeName:    windows.UTF16ToString(entry.ExeFile[:]),
		}
		if err := windows.Process32Next(snap, &entry); err != nil {
			if errors.Is(err, windows.ERROR_NO_MORE_FILES) {
				break
			}
			return nil, fmt.Errorf("procinfo: Process32Next: %w", err)
		}
	}

	return &windowsSnapshot{procs: procs}, nil
}

// GetProcInfo returns a ProcInfo for the given pid.
// snap must be a non-nil value returned by MakeGlobalSnapshot.
// Returns nil, nil if the pid is not present in the snapshot.
func GetProcInfo(_ context.Context, snap any, pid int32) (*ProcInfo, error) {
	if snap == nil {
		return nil, fmt.Errorf("procinfo: GetProcInfo requires a snapshot on windows")
	}
	ws, ok := snap.(*windowsSnapshot)
	if !ok {
		return nil, fmt.Errorf("procinfo: invalid snapshot type")
	}
	si, found := ws.procs[pid]

View on GitHub (pinned to a4447c1563)

Solutions

1. Confirm the wrapped error is not ERROR_NO_MORE_FILES (library already filters that as normal termination)
2. Retry MakeGlobalSnapshot — most mid-iteration failures are transient
3. Check EDR/AV logs for interference with toolhelp32 APIs and whitelist the binary
4. Close other snapshot handles promptly; avoid holding many snapshots concurrently

Example fix

// after (caller tolerance for partial failures)
snap, err := procinfo.MakeGlobalSnapshot()
if err != nil {
	if strings.Contains(err.Error(), "Process32Next") {
		log.Warn("partial snapshot failure, retrying", "err", err)
		snap, err = procinfo.MakeGlobalSnapshot()
	}
	if err != nil {
		return err
	}
}

snap, err := procinfo.MakeGlobalSnapshot()
if err != nil {
	if strings.Contains(err.Error(), "Process32Next") {
		snap, err = procinfo.MakeGlobalSnapshot()
	}
	if err != nil { return err }
}

When it happens

Trigger: MakeGlobalSnapshot when windows.Process32Next returns an error other than windows.ERROR_NO_MORE_FILES — typically ERROR_ACCESS_DENIED from EDR/AV interference or a corrupted snapshot handle mid-iteration.

Common situations: Security software terminating snapshot enumeration; processes churning so fast the snapshot handle becomes invalid; handle corruption in long-running services making thousands of snapshots.

Related errors

• procinfo: CreateToolhelp32Snapshot: %w
• procinfo: Process32First: %w
• --pid flag is not supported on Windows
• failed to create WSL command
• failed to start command: %w

AI-assisted analysis of wavetermdev/waveterm@a4447c1563 (2026-09-01). Data as JSON: /api/errors/2b2cffd9a8e228f1. Report an issue: GitHub.