GimpThumb-utils: GIMP Thumbnail Library Reference Manual

## GimpThumb-utils GimpThumb-utils — Utility functions provided and used by libgimpthumb |

## Functions

gboolean | gimp_thumb_init ()
gchar * | gimp_thumb_find_thumb ()
GimpThumbFileType | gimp_thumb_file_test ()
gchar * | gimp_thumb_name_from_uri ()
gboolean | gimp_thumb_ensure_thumb_dir ()
const gchar * | gimp_thumb_get_thumb_dir ()
void | gimp_thumbs_delete_for_uri ()
gchar * | gimp_thumb_name_from_uri_local ()
gboolean | gimp_thumb_ensure_thumb_dir_local ()
gchar * | gimp_thumb_get_thumb_dir_local ()
void | gimp_thumbs_delete_for_uri_local ()

## Description

Utility functions provided and used by libgimpthumb

## Functions

### gimp_thumb_init ()

    gboolean
    gimp_thumb_init (const gchar *creator,
                     const gchar *thumb_basedir);

This function initializes the thumbnail system. It must be called before any other functions from libgimpthumb are used. You may call it more than once if you want to change the `thumb_basedir` but if you do that, you should make sure that no thread is still using the library. Apart from this function, libgimpthumb is multi-thread safe.

The `creator` string must be 7bit ASCII and should contain the name of the software that creates the thumbnails. It is used to handle thumbnail creation failures. See the spec for more details.

Usually you will pass `NULL` for `thumb_basedir` . Thumbnails will then be stored in the user's personal thumbnail directory as defined in the spec. If you wish to use libgimpthumb to store application-specific thumbnails, you can specify a different base directory here.

#### Parameters

creator | an ASCII string that identifies the thumbnail creator |
thumb_basedir | an absolute path or `NULL` to use the default |

#### Returns

`TRUE` if the library was successfully initialized.

### gimp_thumb_find_thumb ()

    gchar *
    gimp_thumb_find_thumb (const gchar *uri,
                           GimpThumbSize *size);

This function attempts to locate a thumbnail for the given `uri` . First it tries the size that is stored at `size` . If no thumbnail of that size is found, it will look for a larger thumbnail, then falling back to a smaller size.

If the user's thumbnail repository doesn't provide a thumbnail but a local thumbnail repository exists for the folder the image is located in, the same search is done among the local thumbnails (if there are any).

If a thumbnail is found, it's size is written to the variable pointer to by `size` and the file location is returned.

#### Parameters

uri | an escaped URI |
size | pointer to a GimpThumbSize |

#### Returns

a newly allocated string in the encoding of the filesystem or `NULL` if no thumbnail for `uri` was found

### gimp_thumb_file_test ()

    GimpThumbFileType
    gimp_thumb_file_test (const gchar *filename,
                          gint64 *mtime,
                          gint64 *size,
                          gint *err_no);

This is a convenience and portability wrapper around `stat()`. It checks if the given `filename` exists and returns modification time and file size in 64bit integer values.

#### Parameters

filename | a filename in the encoding of the filesystem |
mtime | return location for modification time |
size | return location for file size |
err_no | return location for system "errno" |

#### Returns

The type of the file, or GIMP_THUMB_FILE_TYPE_NONE if the file doesn't exist.

### gimp_thumb_name_from_uri ()

    gchar *
    gimp_thumb_name_from_uri (const gchar *uri,
                              GimpThumbSize size);

Creates the name of the thumbnail file of the specified `size` that belongs to an image file located at the given `uri` .

#### Parameters

uri | an escaped URI |
size | a GimpThumbSize |

#### Returns

a newly allocated filename in the encoding of the filesystem or `NULL` if `uri` points to the user's thumbnail repository.

### gimp_thumb_ensure_thumb_dir ()

    gboolean
    gimp_thumb_ensure_thumb_dir (GimpThumbSize size,
                                 GError **error);

This function checks if the directory that is required to store thumbnails for a particular `size` exist and attempts to create it if necessary.

You shouldn't have to call this function directly since `gimp_thumbnail_save_thumb()` and `gimp_thumbnail_save_failure()` will do this for you.

#### Parameters

size | a GimpThumbSize |
error | return location for possible errors |

#### Returns

`TRUE` is the directory exists, `FALSE` if it could not be created

### gimp_thumb_get_thumb_dir ()

    const gchar *
    gimp_thumb_get_thumb_dir (GimpThumbSize size);

Retrieve the name of the thumbnail folder for a specific size. The returned pointer will become invalid if `gimp_thumb_init()` is used again. It must not be changed or freed.

#### Parameters

size | a GimpThumbSize |

#### Returns

the thumbnail directory in the encoding of the filesystem

### gimp_thumbs_delete_for_uri ()

    void
    gimp_thumbs_delete_for_uri (const gchar *uri);

Deletes all thumbnails for the image file specified by `uri` from the user's thumbnail repository.

#### Parameters

uri | an escaped URI |

Since: GIMP 2.2

### gimp_thumb_name_from_uri_local ()

    gchar *
    gimp_thumb_name_from_uri_local (const gchar *uri,
                                    GimpThumbSize size);

Creates the name of a local thumbnail file of the specified `size` that belongs to an image file located at the given `uri` . Local thumbnails have been introduced with version 0.7 of the spec.

#### Parameters

uri | an escaped URI |
size | a GimpThumbSize |

#### Returns

a newly allocated filename in the encoding of the filesystem or `NULL` if `uri` is a remote file or points to the user's thumbnail repository.

Since: GIMP 2.2

### gimp_thumb_ensure_thumb_dir_local ()

    gboolean
    gimp_thumb_ensure_thumb_dir_local (const gchar *dirname,
                                       GimpThumbSize size,
                                       GError **error);

This function checks if the directory that is required to store local thumbnails for a particular `size` exist and attempts to create it if necessary.

You shouldn't have to call this function directly since `gimp_thumbnail_save_thumb_local()` will do this for you.

#### Parameters

dirname | the basename of the dir, without the actual dirname itself |
size | a GimpThumbSize |
error | return location for possible errors |

#### Returns

`TRUE` is the directory exists, `FALSE` if it could not be created

Since: GIMP 2.2

### gimp_thumb_get_thumb_dir_local ()

    gchar *
    gimp_thumb_get_thumb_dir_local (const gchar *dirname,
                                    GimpThumbSize size);

Retrieve the name of the local thumbnail folder for a specific size. Unlike `gimp_thumb_get_thumb_dir()` the returned string is not constant and should be free'd when it is not any longer needed.

#### Parameters

dirname | the basename of the dir, without the actual dirname itself |
size | a GimpThumbSize |

#### Returns

the thumbnail directory in the encoding of the filesystem

Since: GIMP 2.2

### gimp_thumbs_delete_for_uri_local ()

    void
    gimp_thumbs_delete_for_uri_local (const gchar *uri);

Deletes all thumbnails for the image file specified by `uri` from the local thumbnail repository.

#### Parameters

uri | an escaped URI |

Since: GIMP 2.2

## Types and Values