TIFFCreateDirectory — LibTIFF 4.7.1 documentation

# TIFFCreateDirectory

## Synopsis

    #include <tiffio.h>

int TIFFCreateDirectory(TIFF *tif)

int TIFFFreeDirectory(TIFF *tif)

int TIFFUnlinkDirectory(TIFF *tif, tdir_t dirn)

## Description

The following routines create or release a directory.

`TIFFCreateDirectory()` setup for a directory in a open TIFF file. The newly created directory will not exist on the file till `TIFFWriteDirectory()`, `TIFFCheckpointDirectory()`, `TIFFFlush()` or `TIFFClose()` is called. `TIFFWriteDirectory()` also creates a new directory, frees the `*tif` structure and sets up a new one.

`TIFFFreeDirectory()` releases allocated storage associated with a directory, especially custom-fields. However, the main part of the directory is not touched. Routine `TIFFCleanup()` calls `TIFFFreeDirectory()` to release the directory part of the tif structure.

`TIFFUnlinkDirectory()` unlink the specified directory from the directory chain. The parameter dirn specifies the subfile/directory as an integer number, with the first directory numbered one (1). This is different to `TIFFSetDirectory()` or `TIFFCurrentDirectory()` where the first directory starts with zero (0).

Directory query functions `TIFFCurrentDirectory()`, `TIFFCurrentDirOffset()`, `TIFFLastDirectory()` and `TIFFNumberOfDirectories()` retrieve information about directories in an open TIFF file. Be aware that until a directory is not written to file AND read back, the query functions won't retrieve the correct information!

## Notes

Be aware:

- that until a directory is not written to file AND read back, the query functions won't retrieve the correct information!

- that the newly created directory will not exist on the file till `TIFFWriteDirectory()`, `TIFFCheckpointDirectory()`, `TIFFFlush()` or `TIFFClose()` has been called.

- that `TIFFCreateDirectory()` and `TIFFWriteDirectory()` create a new directory, free the `*tif` structure and set up a new one.

- that unlike `TIFFWriteDirectory()`, `TIFFCheckpointDirectory()` does not free up the directory data structures in memory.

After `libtiff` version 4.6.0 `TIFFCreateDirectory()` also releases the directory part of the tif structure by calling `TIFFFreeDirectory()`, which should have been called by the user application before creating a new directory.

## Diagnostics

All error messages are directed to the `TIFFErrorExtR()` routine. Likewise, warning messages are directed to the `TIFFWarningExtR()` routine.

## See also

libtiff (3tiff), TIFFCustomDirectory (3tiff), TIFFquery (3tiff), TIFFSetDirectory (3tiff), TIFFWriteDirectory (3tiff)