---
name: "TIFFCustomTagList"
section: "3tiff"
platform: "linux"
package: "libtiff-dev"
version: "4.7.0-3+deb13u3"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/TIFFCustomTagList"
---

# TIFFCustomTagList(3tiff)

returns information about the custom tag list

## NAME

TIFFCustomTagList - returns information about the custom tag list

## SYNOPSIS

```
#include <tiffio.h>
```

- **int TIFFGetTagListCount(TIFF \*tif)**

  - **uint32\_t TIFFGetTagListEntry(TIFF \*tif, int tag\_index)**

  ## DESCRIPTION

*TIFFGetTagListCount()* returns the number of entries in the custom tag list.

*TIFFGetTagListEntry()* returns the tag number of the (n.th - 1) entry within the custom tag list. If the **tag\_index** is larger or equal to the number of entries in the tag list 0xFFFFFFFF *(=(uint32\_t(-1))* is returned.

## NOTE

The known tags to **libtiff** are define as 'named' tags and a lot of them as *custom* tags. The custom tag definitions are handled in an internal custom tag list. This list can also be extended by adding tag definitions to that list, so that **libtiff** is aware of those tags. See *Defining Application Tags*

## DIAGNOSTICS

none

## SEE ALSO

*libtiff* (3tiff), *TIFFOpen*  (3tiff), *TIFFError* (3tiff)

## AUTHOR

LibTIFF contributors

## COPYRIGHT

1988-2022, LibTIFF contributors