### ImageMagick version

7.1.1-32

### Operating system

Linux

### Operating system, version and so on

Debian

### Description

Example on https://www.imagemagick.org/Magick++/Pixels.html is broken, see steps to reproduce.

### Steps to Reproduce

```shell
$ g++ \
	-DMAGICKCORE_HDRI_ENABLE=1 \
	-DMAGICKCORE_QUANTUM_DEPTH=8 \
	-DMAGICKCORE_CHANNEL_MASK_DEPTH=32 \
	-I./include/ImageMagick-7 \
	-L./lib \
	-lMagickCore-7.Q8HDRI \
	-lMagick++-7.Q8HDRI \
	-lMagickWand-7.Q8HDRI \
	-lgomp \
	main.c \
	./lib/libMagick++-7.Q8HDRI.a \
	./lib/libMagickWand-7.Q8HDRI.a \
	./lib/libMagickCore-7.Q8HDRI.a \
	/lib/x86_64-linux-gnu/libgomp.so.1 -o main

$ ./main 
terminate called after throwing an instance of 'Magick::ErrorMissingDelegate'
  what():  main: no encode delegate for this image format `XC' @ error/constitute.c/WriteImage/1409
Aborted
```

### Images

_No response_
Outdated Magick++ Pixels documentation
This is a GitHub Issue
repo:ImageMagick
owner:ImageMagick
Title : Outdated Magick++ Pixels documentation
Issue date:

--- start body ---
### ImageMagick version

7.1.1-32

### Operating system

Linux

### Operating system, version and so on

Debian

### Description

Example on https://www.imagemagick.org/Magick++/Pixels.html is broken, see steps to reproduce.

### Steps to Reproduce

```shell
$ g++ \
	-DMAGICKCORE_HDRI_ENABLE=1 \
	-DMAGICKCORE_QUANTUM_DEPTH=8 \
	-DMAGICKCORE_CHANNEL_MASK_DEPTH=32 \
	-I./include/ImageMagick-7 \
	-L./lib \
	-lMagickCore-7.Q8HDRI \
	-lMagick++-7.Q8HDRI \
	-lMagickWand-7.Q8HDRI \
	-lgomp \
	main.c \
	./lib/libMagick++-7.Q8HDRI.a \
	./lib/libMagickWand-7.Q8HDRI.a \
	./lib/libMagickCore-7.Q8HDRI.a \
	/lib/x86_64-linux-gnu/libgomp.so.1 -o main

$ ./main 
terminate called after throwing an instance of 'Magick::ErrorMissingDelegate'
  what():  main: no encode delegate for this image format `XC' @ error/constitute.c/WriteImage/1409
Aborted
```

### Images

_No response_
--- end body ---
