Queries (XForms (Forms Library) - Version 1.2 (Rev. 4) A Graphical User Interface Toolkit for X)

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#### 37.5.3 Queries

Since the number of formats supported by the library is dynamic in nature, some query routines are available to obtain support information.

To obtain the number of currently supported image formats, use the routine

    int flimage_get_number_of_formats(void);

The functions returns the number of formats supported, for reading or writing or both. To obtain detailed information for each format, the following can be used

    typedef struct {
        const char * formal_name;
        const char * short_name;
        const char * extension;
        int          type;
        int          read_write;
        int          annotation;
    } FLIMAGE_FORMAT_INFO;

    const FLIMAGE_FORMAT_INFO *flimage_get_format_info(int n);

where parameter `n` is an integer between 1 and the return value of `flimage_get_number_of_formats()` . Upon function return a static buffer is returned containing the basic information about the image. The read_write field can be one of the following combinations thereof

`FLIMAGE_READABLE`

  supports reading

`FLIMAGE_WRITABLE`

  supports writing

or the bitwise OR of both.

These two routines are most useful for reporting or presenting capabilities to the user

    FLIMAGE_FORMAT_INFO *info;
    int n = flimage_get_number_of_formats();

    fprintf(stderr,"FL supports the following format\n");
    for (; n; n--) {
        info = flimage_get_format_info(n);
        fprintf(stderr,"%s format\t(%c%c)\n",
                info->short_name,
                (info->read_write & FLIMAGE_READABLE) ? 'r' : ' ',
                (info->read_write & FLIMAGE_WRITABLE) ? 'w' : ' ');
    }