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

# TIFFquery(3tiff)

query routines

## NAME

TIFFquery - query routines

## SYNOPSIS

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

- **tdir\_t TIFFCurrentDirectory(TIFF \*tif)**

  - **uint64\_t TIFFCurrentDirOffset(TIFF \*tif)**

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

  - **tdir\_t TIFFNumberOfDirectories(TIFF \*tif)**

  - **uint32\_t TIFFCurrentRow(TIFF \*tif)**

  - **tstrip\_t TIFFCurrentStrip(TIFF \*tif)**

  - **ttile\_t TIFFCurrentTile(TIFF \*tif)**

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

  - **char \*TIFFFileName(TIFF \*tif)**

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

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

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

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

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

  - **int TIFFIsMSB2LSB(TIFF \*tif)**

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

  - **const char \*TIFFGetVersion(void)**

  ## DESCRIPTION

The following query routines return status information about the directory structure of an open TIFF file.

*TIFFCurrentDirectory()* returns the index of the current *Image File Directory (IFD)*. Directories are numbered starting at 0. This number is suitable for use with the *TIFFSetDirectory()* routine. There are *IFDs* in the file and an "active" *IFD*  in memory, from which fields are "set" and "get". The index of the current directory returned is:

- a.

  65535 (non-existing directory) if there is no IFD in the file after opening, or the state is unknown, or the last read (i.e. TIFFFetchDirectory()) failed, or a custom directory was written.

- b.

  IFD index of last IFD written in the file. In this case the active IFD is a new (empty) one and the current directory offset from TIFFCurrentDirOffset() is zero. If writing fails, the IFD index is not changed.

- c.

  IFD index of IFD read from file into memory (=active IFD), even if IFD is corrupt and TIFFReadDirectory() returns 0. Then the current directory offset is the offset of the IFD in the file.

- d.

  IFD index „0“, whenever a custom directory or an unchained SubIFD was read.

*TIFFCurrentDirOffset()* returns the file offset of the current directory (instead of an index). The file offset is suitable for use with the *TIFFSetSubDirectory()* routine. This is required for accessing subdirectories linked through a **SubIFD** tag. See also *SubIFD access*.

*TIFFLastDirectory()* returns a non-zero value if the current directory is the last directory in the file; otherwise zero is returned. A new (empty) directory in the memory (after *TIFFWriteDirectory()* or *TIFFCreateDirectory()*) also counts as the last directory, even if it has not yet been written to a file.

*TIFFNumberOfDirectories()* returns the number of directories in a file. Be aware that just created directories, which are not "written" to file do not count.

**NOTE:**

Be aware that the return value of the above directory query functions is not valid until the directory is "written" to file AND read back e.g. *TIFFSetDirectory()* or *TIFFReadDirectory()*.

The following query routines return information about an open TIFF file and its image data.

*TIFFCurrentRow()*, *TIFFCurrentStrip()*, and *TIFFCurrentTile()* return the current row, strip, and tile, respectively, that is being read or written. These values are updated each time a read or write is done.

*TIFFFileno()* returns the underlying file descriptor used to access the TIFF image in the filesystem.

*TIFFFileName()* returns the pathname argument passed to *TIFFOpen()* or *TIFFFdOpen()*.

*TIFFGetMode()* returns the mode with which the underlying file was opened. On UNIX systems, this is the value passed to the **open()** (2) system call.

*TIFFIsTiled()* returns a non-zero value if the image data has a tiled organization. Zero is returned if the image data is organized in strips.

*TIFFIsBigEndian()* returns a non-zero value if the file is BigEndian and zero if the file is LittleEndian.

*TIFFIsBigTIFF()* returns a non-zero value if the file is in BigTIFF style.

*TIFFIsByteSwapped()* returns a non-zero value if the image data was in a different byte-order than the host machine. Zero is returned if the TIFF file and local host byte-orders are the same.  Note that *TIFFReadTile()*, *TIFFReadEncodedStrip()* and *TIFFReadScanline()* functions already normally perform byte swapping to local host order if needed.

*TIFFIsMSB2LSB()* returns a non-zero value if the image data is being returned with bit 0 as the most significant bit.

*TIFFIsUpSampled()* returns a non-zero value if image data returned through the read interface routines is being up-sampled. This can be useful to applications that want to calculate I/O buffer sizes to reflect this usage (though the usual strip and tile size routines already do this).

*TIFFGetVersion()* returns an **ASCII** string that has a version stamp for the TIFF library software.

## DIAGNOSTICS

None.

## SEE ALSO

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

## AUTHOR

LibTIFF contributors

## COPYRIGHT

1988-2022, LibTIFF contributors