---
name: "debug_heartbeat"
section: "3tcl"
platform: "linux"
package: "tcllib"
version: "2.0+dfsg-4"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/debug_heartbeat"
---

# debug\_heartbeat(3tcl)

debug narrative - heartbeat

```

```

## NAME

debug::heartbeat - debug narrative - heartbeat

## SYNOPSIS

package require **Tcl 8.5 9**

package require **debug::heartbeat ?1.0.2?**

package require **debug ?1?**

**debug** **heartbeat** ?*delta*?

```

```

## DESCRIPTION

## API

- **debug** **heartbeat** ?*delta*?

  This method activates or disables a heartbeat with which to monitor the event loop of an event-based Tcl application.

  It reserves the debug tag **heartbeat** for its operation and writes a message every *delta* milliseconds.

  A *delta*-value \<= 0 disables the heartbeat.

  The message produced by the heartbeat contains a sequence counter and the time in milliseconds since the last beat, thus providing insight into timing variationsn and deviations from the nominal *delta*.

## BUGS, IDEAS, FEEDBACK

This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category *debug* of the *Tcllib Trackers* \[http://core.tcl.tk/tcllib/reportlist\]. Please also report any ideas for enhancements you may have for either package and/or documentation.

When proposing code changes, please provide *unified diffs*, i.e the output of **diff -u**.

Note further that *attachments* are strongly preferred over inlined patches. Attachments can be made by going to the **Edit** form of the ticket immediately after its creation, and then using the left-most button in the secondary navigation bar.

## KEYWORDS

debug, heartbeat, log, narrative, trace

## CATEGORY

debugging, tracing, and logging

## COPYRIGHT

```
Copyright (c) 200?, Colin McCormack, Wub Server Utilities
Copyright (c) 2012, Andreas Kupries <andreas_kupries@users.sourceforge.net>
```