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/*! \file exif.h exif/exif.h
* \brief Dummy header file for documentation purposes
* \date 2007
* \author Hans Ulrich Niedermann, et. al.
*
* \mainpage The libexif library
*
* \section general_notes General Notes
*
* This documentation is work in progress, as is the code itself.
*
* \section using_libexif Using libexif
*
* \#include <libexif/exif-data.h>
*
* libexif provides a libexif.pc file for use with pkgconfig on the
* libexif installation. If you are using libtool to build your
* package, you can also make use of libexif-uninstalled.pc.
*
* An application using libexif would typically first create an #ExifLoader to
* load EXIF data into memory. From there, it would extract that data as
* an #ExifData to start manipulating it. Each IFD is represented by its own
* #ExifContent within that #ExifData, which contains all the tag data in
* #ExifEntry form. If the MakerNote data is required, an #ExifMnoteData
* can be extracted from the #ExifData and manipulated with the MakerNote
* functions.
*
* libexif is written in C using an object-based style that defines
* sets of functions that operate on each data structure.
*
* \section data_structures Primary Data Structures
*
* #ExifLoader
* State maintained by the loader interface while importing EXIF data
* from an external file or memory
*
* #ExifData
* The entirety of EXIF data found in an image
*
* #ExifContent
* All EXIF tags in a single IFD
*
* #ExifEntry
* Data found in a single EXIF tag
*
* #ExifMnoteData
* All data found in the MakerNote tag
*
* #ExifLog
* State maintained by the logging interface
*
* \section string_conventions String Conventions
*
* Strings are 8 bit characters ("char*"). When libexif is compiled with
* NLS, character set and encoding are as set in the current locale,
* except for strings that come directly from the data in EXIF
* tags which are generally returned in raw form. Most EXIF strings are
* defined to be plain 7-bit ASCII so this raw form should be acceptable in
* any UNIX locale, but some software ignores the specification and
* writes 8-bit characters. It is up to the application to detect this
* and deal with it intelligently.
*
* \section memory_management Memory Management Patterns
*
* For pointers to data objects, libexif uses reference counting. The
* pattern is to use the foo_new() function to create a data object,
* foo_ref() to increase the reference counter, and foo_unref() to
* decrease the reference counter and possibly free(3)ing the memory.
*
* Libexif by default relies on the calloc(3), realloc(3), and free(3)
* functions, but the libexif user can tell libexif to use their
* special memory management functions at runtime.
*
* \section thread_safety Thread Safety
*
* libexif is thread safe when the underlying C library is also thread safe.
* Some C libraries may require defining a special macro (like _REENTRANT)
* to ensure this, or may require linking to a special thread-safe version of
* the library.
*
* The programmer must ensure that each object allocated by libexif is only
* used in a single thread at once. For example, an ExifData* allocated
* in one thread can't be used in a second thread if there is any chance
* that the first thread could use it at the same time. Multiple threads
* can use libexif without issues if they never share handles.
*
*/
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