---
name: "observe"
section: "3tk"
platform: "linux"
package: "tkcon"
version: "2:2.7.11-6"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/observe/3tk"
---

# observe(3tk)

Runtime debugging output in TkCon

```

```

## NAME

observe - Runtime debugging output in TkCon

## SYNOPSIS

**observe** *command* *cmdname* ?*maxlevel*?

**observe** *cdelete* *cmdname*

**observe** *cinfo* *cmdname*

**observe** *variable* *varname* *operation* ?*args*?

**observe** *vdelete* *varname* *operation*

**observe** *vinfo* *varname*

```

```

## DESCRIPTION

This command provides runtime debugging output for variables and commands without the need to edit your code. For variables, the underlying mechanism uses **trace** and **dump** var. For commands, it renames the observed procedure and uses a special wrapper procedure. WARNING: using this procedure after checkpointing state will result in major problems if you clean state because the renamed (true) commands will be lost.

This procedure is experimental. Comments are encouraged.

- **observe** *command* *cmdname* ?*maxlevel*?

  This will create a wrapper command which prints out (using **dump**) the call stack to the console. maxlevel represents the maximum number of levels of the call stack which will be printed (defaults to 4).

- **observe** *cdelete* *cmdname*

  Removes the wrapper around an observed command.

- **observe** *cinfo* *cmdname*

  Prints out useless info.

- **observe** *variable* *varname* *operation* ?*args*?

  Currently a wrapper around trace that uses **dump** to print out the value of the named variable whenever the specified operation on that variable occurs (must be *read*, *write* or *unset*).

- **observe** *vdelete* *varname* *operation*

  Deletes the trace wrapper around the named variable.

- **observe** *vinfo* *varname*

  Prints out trace info about the named variable.

## SEE ALSO

[**dump**(3tk)](/dump/3tk.md), [**idebug**(3tk)](/idebug/3tk.md), [**tkcon**(1)](/tkcon/1.md), [**tkcon**(3tk)](/tkcon/3tk.md), [**tkconrc**(5)](/tkconrc/5.md)

## KEYWORDS

Tk, console, debug

## COPYRIGHT

```
Copyright (c) Jeffrey Hobbs <jeff at hobbs.org>
```