|  | 
 NAME     
 |  |  |  | parsehtml, printitems, validitems, freeitems, freedocinfo, dimenkind,
    dimenspec, targetid, targetname, fromStr, toStr – HTML parser 
 | 
 SYNOPSIS     
 |  |  |  | #include <u.h> #include <libc.h>
 #include <html.h>
 Item*    parsehtml(uchar* data, int datalen, Rune* src, int mtype,
 
 void    printitems(Item* items, char* msg)|  |  |  | |  |  |  | int chset, Docinfo** pdi) 
 | 
 | 
 int     validitems(Item* items)
 void    freeitems(Item* items)
 void    freedocinfo(Docinfo* d)
 int     dimenkind(Dimen d)
 int     dimenspec(Dimen d)
 int     targetid(Rune* s)
 Rune*    targetname(int targid)
 uchar* fromStr(Rune* buf, int n, int chset)
 Rune*    toStr(uchar* buf, int n, int chset)
 
 | 
 DESCRIPTION     
 |  |  |  | This library implements a parser for HTML 4.0 documents. The parsed
    HTML is converted into an intermediate representation that describes
    how the formatted HTML should be laid out. 
    
    
    Parsehtml parses an entire HTML document contained in the buffer
    data and having length datalen. The URL of the document should
    be passed in as src. Mtype is the media type of the document,
    which should be either TextHtml or TextPlain. The character set
    of the document is described in chset, which can be one of US_Ascii,
    ISO_8859_1,
    UTF_8 or Unicode. The return value is a linked list of Item structures,
    described in detail below. As a side effect, *pdi is set to point
    to a newly created Docinfo structure, containing information pertaining
    to the entire document. 
    
    
    The library expects two allocation routines to be provided by
    the caller, emalloc and erealloc. These routines are analogous
    to the standard malloc and realloc routines, except that they
    should not return if the memory allocation fails. In addition,
    emalloc is required to zero the memory. 
    
    
    For debugging purposes, printitems may be called to display the
    contents of an item list; individual items may be printed using
    the %I print verb, installed on the first call to parsehtml. validitems
    traverses the item list, checking that all of the pointers are
    valid. It returns 1 is everything is ok, and 0 if an error was
    found. Normally, one would not call these
    routines directly. Instead, one sets the global variable dbgbuild
    and the library calls them automatically. One can also set warn,
    to cause the library to print a warning whenever it finds a problem
    with the input document, and dbglex, to print debugging information
    in the lexer. 
    
    
    When an item list is finished with, it should be freed with freeitems.
    Then, freedocinfo should be called on the pointer returned in
    *pdi. 
    
    
    Dimenkind and dimenspec are provided to interpret the Dimen type,
    as described in the section Dimension Specifications. 
    
    
    Frame target names are mapped to integer ids via a global, permanent
    mapping. To find the value for a given name, call targetid, which
    allocates a new id if the name hasn’t been seen before. The name
    of a given, known id may be retrieved using targetname. The library
    predefines FTtop, FTself, FTparent and FTblank. 
    
    
    The library handles all text as Unicode strings (type Rune*).
    Character set conversion is provided by fromStr and toStr. FromStr
    takes n Unicode characters from buf and converts them to the character
    set described by chset. ToStr takes n bytes from buf, interpretted
    as belonging to character set chset, and converts them to a Unicode
    string. Both
    routines null-terminate the result, and use emalloc to allocate
    space for it. 
 Items     typedef struct Item Item;The return value of parsehtml is a linked list of variant structures,
    with the generic portion described by the following definition:
 struct Item
 {
 
 };|  |  |  | Item*     next; int       width;
 int       height;
 int       ascent;
 int       anchorid;
 int       state;
 Genattr* genattr;
 int       tag;
 
 | 
 The field next points to the successor in the linked list of items,
    while width, height, and ascent are intended for use by the caller
    as part of the layout process. Anchorid, if non-zero, gives the
    integer id assigned by the parser to the anchor that this item
    is in (see section Anchors). State is a collection of flags and
    values described as follows: 
    
    
    enum
 {
 
 };|  |  |  | IFbrk =         0x80000000, IFbrksp =       0x40000000,
 IFnobrk =       0x20000000,
 IFcleft =       0x10000000,
 IFcright =       0x08000000,
 IFwrap =        0x04000000,
 IFhang =        0x02000000,
 IFrjust =       0x01000000,
 IFcjust =       0x00800000,
 IFsmap =        0x00400000,
 IFindentshift = 8,
 IFindentmask =    (255<<IFindentshift),
 IFhangmask =     255
 
 | 
 IFbrk is set if a break is to be forced before placing this item.
    IFbrksp is set if a 1 line space should be added to the break
    (in which case IFbrk is also set). IFnobrk is set if a break is
    not permitted before the item. IFcleft is set if left floats should
    be cleared (that is, if the list of pending left floats should
    be placed) before this item is placed, and
    IFcright is set for right floats. In both cases, IFbrk is also
    set. IFwrap is set if the line containing this item is allowed
    to wrap. IFhang is set if this item hangs into the left indent.
    IFrjust is set if the line containing this item should be right
    justified, and IFcjust is set for center justified lines. IFsmap
    is used to indicate that an image is a server-
    side map. The low 8 bits, represented by IFhangmask, indicate
    the current hang into left indent, in tenths of a tabstop. The
    next 8 bits, represented by IFindentmask and IFindentshift, indicate
    the current indent in tab stops. 
    
    
    The field genattr is an optional pointer to an auxiliary structure,
    described in the section Generic Attributes. 
    
    
    Finally, tag describes which variant type this item has. It can
    have one of the values Itexttag, Iruletag, Iimagetag, Iformfieldtag,
    Itabletag, Ifloattag or Ispacertag. For each of these values,
    there is an additional structure defined, which includes Item
    as an unnamed initial substructure, and then defines additional
    fields. 
    
    
    Items of type Itexttag represent a piece of text, using the following
    structure: 
    
    
    struct Itext
 {
 
 };|  |  |  | Item; Rune* s;
 int    fnt;
 int    fg;
 uchar voff;
 uchar ul;
 
 | 
 Here s is a null-terminated Unicode string of the actual characters
    making up this text item, fnt is the font number (described in
    the section Font Numbers), and fg is the RGB encoded color for
    the text. Voff measures the vertical offset from the baseline;
    subtract Voffbias to get the actual value (negative values represent
    a displacement down the
    page). The field ul is the underline style: ULnone if no underline,
    ULunder for conventional underline, and ULmid for strike-through.
    
    
    
    Items of type Iruletag represent a horizontal rule, as follows:
    
    
    
    struct Irule
 {
 
 };|  |  |  | Item; uchar align;
 uchar noshade;
 int    size;
 Dimen wspec;
 
 | 
 Here align is the alignment specification (described in the corresponding
    section), noshade is set if the rule should not be shaded, size
    is the height of the rule (as set by the size attribute), and
    wspec is the desired width (see section Dimension Specifications).
    
    
    
    Items of type Iimagetag describe embedded images, for which the
    following structure is defined: 
    
    
    struct Iimage
 {
 
 };|  |  |  | Item; Rune*    imsrc;
 int      imwidth;
 int      imheight;
 Rune*    altrep;
 Map*     map;
 int      ctlid;
 uchar    align;
 uchar    hspace;
 uchar    vspace;
 uchar    border;
 Iimage* nextimage;
 
 | 
 Here imsrc is the URL of the image source, imwidth and imheight,
    if non-zero, contain the specified width and height for the image,
    and altrep is the text to use as an alternative to the image,
    if the image is not displayed. Map, if set, points to a structure
    describing an associated client-side image map. Ctlid is reserved
    for use by the application,
    for handling animated images. Align encodes the alignment specification
    of the image. Hspace contains the number of pixels to pad the
    image with on either side, and Vspace the padding above and below.
    Border is the width of the border to draw around the image. Nextimage
    points to the next image in the document (the head of this list
    is
    Docinfo.images). 
    
    
    For items of type Iformfieldtag, the following structure is defined:
    
    
    
    struct Iformfield
 {
 
 };|  |  |  | Item; Formfield* formfield;
 
 | 
 This adds a single field, formfield, which points to a structure
    describing a field in a form, described in section Forms. 
    
    
    For items of type Itabletag, the following structure is defined:
    
    
    
    struct Itable
 {
 };
 Table points to a structure describing the table, described in
    the section Tables. 
    
    
    For items of type Ifloattag, the following structure is defined:
    
    
    
    struct Ifloat
 {
 
 };|  |  |  | Item; Item*    item;
 int      x;
 int      y;
 uchar    side;
 uchar    infloats;
 Ifloat* nextfloat;
 
 | 
 The item points to a single item (either a table or an image)
    that floats (the text of the document flows around it), and side
    indicates the margin that this float sticks to; it is either ALleft
    or ALright. X and y are reserved for use by the caller; these
    are typically used for the coordinates of the top of the float.
    Infloats is used by the caller to keep
    track of whether it has placed the float. Nextfloat is used by
    the caller to link together all of the floats that it has placed.
    
    
    
    For items of type Ispacertag, the following structure is defined:
    
    
    
    struct Ispacer
 {
 };
 Spkind encodes the kind of spacer, and may be one of ISPnull (zero
    height and width), ISPvline (takes on height and ascent of the
    current font), ISPhspace (has the width of a space in the current
    font) and ISPgeneral (for all other purposes, such as between
    markers and lists).
 
 Generic Attributes    The genattr field of an item, if non-nil, points to a structure
    that holds the values of attributes not specific to any particular
    item type, as they occur on a wide variety of underlying HTML
    tags. The structure is as follows: 
    
    
    typedef struct Genattr Genattr;
 struct Genattr
 {
 
 };|  |  |  | Rune*    id; Rune*    class;
 Rune*    style;
 Rune*    title;
 SEvent* events;
 
 | 
 Fields id, class, style and title, when non-nil, contain values
    of correspondingly named attributes of the HTML tag associated
    with this item. Events is a linked list of events (with corresponding
    scripted actions) associated with the item: 
    
    
    typedef struct SEvent SEvent;
 struct SEvent
 {
 
 };|  |  |  | SEvent* next; int      type;
 Rune*    script;
 
 | 
 Here, next points to the next event in the list, type is one of
    SEonblur, SEonchange, SEonclick, SEondblclick, SEonfocus, SEonkeypress,
    SEonkeyup, SEonload, SEonmousedown, SEonmousemove, SEonmouseout,
    SEonmouseover, SEonmouseup, SEonreset, SEonselect, SEonsubmit
    or SEonunload, and script is the text of
    the associated script.
 
 Dimension Specifications    Some structures include a dimension specification, used where
    a number can be followed by a % or a * to indicate percentage
    of total or relative weight. This is encoded using the following
    structure: 
    
    
    typedef struct Dimen Dimen;
 struct Dimen
 {
 };
 Separate kind and spec values are extracted using dimenkind and
    dimenspec. Dimenkind returns one of Dnone, Dpixels, Dpercent or
    Drelative. Dnone means that no dimension was specified. In all
    other cases, dimenspec should be called to find the absolute number
    of pixels, the percentage of total, or the relative weight.
 Background Specifications    It is possible to set the background of the entire document, and
    also for some parts of the document (such as tables). This is
    encoded as follows: 
    
    
    typedef struct Background Background;
 struct Background
 {
 };
 Image, if non-nil, is the URL of an image to use as the background.
    If this is nil, color is used instead, as the RGB value for a
    solid fill color.
 
 Alignment Specifications    Certain items have alignment specifiers taken from the following
    enumerated type: 
    
    
    enum
 {
 
 };|  |  |  | ALnone = 0, ALleft, ALcenter, ALright, ALjustify, ALchar, ALtop, ALmiddle, ALbottom, ALbaseline
 
 | 
 These values correspond to the various alignment types named in
    the HTML 4.0 standard. If an item has an alignment of ALleft or
    ALright, the library automatically encapsulates it inside a float
    item. 
    
    
    Tables, and the various rows, columns and cells within them, have
    a more complex alignment specification, composed of separate vertical
    and horizontal alignments: 
    
    
    typedef struct Align Align;
 struct Align
 {
 
 };|  |  |  | uchar halign; uchar valign;
 
 | 
 Halign can be one of ALnone, ALleft, ALcenter, ALright, ALjustify
    or ALchar. Valign can be one of ALnone, ALmiddle, ALbottom, ALtop
    or ALbaseline.
 
 Font Numbers    Text items have an associated font number (the fnt field), which
    is encoded as style*NumSize+size. Here, style is one of FntR,
    FntI, FntB or FntT, for roman, italic, bold and typewriter font
    styles, respectively, and size is Tiny, Small, Normal, Large or
    Verylarge. The total number of possible font numbers is NumFnt,
    and the default font
    number is DefFnt (which is roman style, normal size).
 
 Document Info    Global information about an HTML page is stored in the following
    structure: 
    
    
    typedef struct Docinfo Docinfo;
 struct Docinfo
 {
 
 };|  |  |  | // stuff from HTTP headers, doc head, and body tag Rune*       src;
 Rune*       base;
 Rune*       doctitle;
 Background    background;
 Iimage*      backgrounditem;
 int         text;
 int         link;
 int         vlink;
 int         alink;
 int         target;
 int         chset;
 int         mediatype;
 int         scripttype;
 int         hasscripts;
 Rune*       refresh;
 Kidinfo*     kidinfo;
 int         frameid;
 // info needed to respond to user actions
 Anchor*      anchors;
 DestAnchor* dests;
 Form*       forms;
 Table*       tables;
 Map*        maps;
 Iimage*      images;
 
 | 
 Src gives the URL of the original source of the document, and
    base is the base URL. Doctitle is the document’s title, as set
    by a <title> element. Background is as described in the section
    Background Specifications, and backgrounditem is set to be an
    image item for the document’s background image (if given as a
    URL), or else nil. Text
    gives the default foregound text color of the document, link the
    unvisited hyperlink color, vlink the visited hyperlink color,
    and alink the color for highlighting hyperlinks (all in 24-bit
    RGB format). Target is the default target frame id. Chset and
    mediatype are as for the chset and mtype parameters to parsehtml.
    Scripttype is the type of any
    scripts contained in the document, and is always TextJavascript.
    Hasscripts is set if the document contains any scripts. Scripting
    is currently unsupported. Refresh is the contents of a <meta http−equiv=Refresh
    ...> tag, if any. Kidinfo is set if this document is a frameset
    (see section Frames). Frameid is this document’s frame id. 
    
    
    Anchors is a list of hyperlinks contained in the document, and
    dests is a list of hyperlink destinations within the page (see
    the following section for details). Forms, tables and maps are
    lists of the various forms, tables and client-side maps contained
    in the document, as described in subsequent sections. Images is
    a list of all the image items in the
    document.
 
 Anchors     The library builds two lists for all of the <a> elements (anchors)
    in a document. Each anchor is assigned a unique anchor id within
    the document. For anchors which are hyperlinks (the href attribute
    was supplied), the following structure is defined: 
    
    
    typedef struct Anchor Anchor;
 struct Anchor
 {
 
 };|  |  |  | Anchor* next; int      index;
 Rune*    name;
 Rune*    href;
 int      target;
 
 | 
 Next points to the next anchor in the list (the head of this list
    is Docinfo.anchors). Index is the anchor id; each item within
    this hyperlink is tagged with this value in its anchorid field.
    Name and href are the values of the correspondingly named attributes
    of the anchor (in particular, href is the URL to go to). Target
    is the value of the target
    attribute (if provided) converted to a frame id. 
    
    
    Destinations within the document (anchors with the name attribute
    set) are held in the Docinfo.dests list, using the following structure:
    
    
    
    typedef struct DestAnchor DestAnchor;
 struct DestAnchor
 {
 
 };|  |  |  | DestAnchor* next; int         index;
 Rune*       name;
 Item*       item;
 
 | 
 Next is the next element of the list, index is the anchor id,
    name is the value of the name attribute, and item is points to
    the item within the parsed document that should be considered
    to be the destination.
 
 Forms     Any forms within a document are kept in a list, headed by Docinfo.forms.
    The elements of this list are as follows: 
    
    
    typedef struct Form Form;
 struct Form
 {
 
 };|  |  |  | Form*       next; int        formid;
 Rune*       name;
 Rune*       action;
 int        target;
 int        method;
 int        nfields;
 Formfield* fields;
 
 | 
 Next points to the next form in the list. Formid is a serial number
    for the form within the document. Name is the value of the form’s
    name or id attribute. Action is the value of any action attribute.
    Target is the value of the target attribute (if any) converted
    to a frame target id. Method is one of HGet or HPost. Nfields
    is the number of fields in the
    form, and fields is a linked list of the actual fields. 
    
    
    The individual fields in a form are described by the following
    structure: 
    
    
    typedef struct Formfield Formfield;
 struct Formfield
 {
 
 };|  |  |  | Formfield* next; int        ftype;
 int        fieldid;
 Form*       form;
 Rune*       name;
 Rune*       value;
 int        size;
 int        maxlength;
 int        rows;
 int        cols;
 uchar       flags;
 Option*     options;
 Item*       image;
 int        ctlid;
 SEvent*     events;
 
 | 
 Here, next points to the next field in the list. Ftype is the
    type of the field, which can be one of Ftext, Fpassword, Fcheckbox,
    Fradio, Fsubmit, Fhidden, Fimage, Freset, Ffile, Fbutton, Fselect
    or Ftextarea. Fieldid is a serial number for the field within
    the form. Form points back to the form containing this field.
    Name, value,
    size, maxlength, rows and cols each contain the values of corresponding
    attributes of the field, if present. Flags contains per-field
    flags, of which FFchecked and FFmultiple are defined. Image is
    only used for fields of type Fimage; it points to an image item
    containing the image to be displayed. Ctlid is reserved for use
    by the caller,
    typically to store a unique id of an associated control used to
    implement the field. Events is the same as the corresponding field
    of the generic attributes associated with the item containing
    this field. Options is only used by fields of type Fselect; it
    consists of a list of possible options that may be selected for
    that field, using the following structure: 
    
    
    typedef struct Option Option;
 struct Option
 {
 
 };|  |  |  | Option* next; int      selected;
 Rune*    value;
 Rune*    display;
 
 | 
 Next points to the next element of the list. Selected is set if
    this option is to be displayed initially. Value is the value to
    send when the form is submitted if this option is selected. Display
    is the string to display on the screen for this option.
 
 Tables     The library builds a list of all the tables in the document, headed
    by Docinfo.tables. Each element of this list has the following
    format: 
    
    
    typedef struct Table Table;
 struct Table
 {
 
 };|  |  |  | Table*       next; int          tableid;
 Tablerow*     rows;
 int          nrow;
 Tablecol*     cols;
 int          ncol;
 Tablecell*    cells;
 int          ncell;
 Tablecell*** grid;
 Align        align;
 Dimen        width;
 int          border;
 int          cellspacing;
 int          cellpadding;
 Background    background;
 Item*        caption;
 uchar        caption_place;
 Lay*         caption_lay;
 int          totw;
 int          toth;
 int          caph;
 int          availw;
 Token*       tabletok;
 uchar        flags;
 
 | 
 Next points to the next element in the list of tables. Tableid
    is a serial number for the table within the document. Rows is
    an array of row specifications (described below) and nrow is the
    number of elements in this array. Similarly, cols is an array
    of column specifications, and ncol the size of this array. Cells
    is a list of all cells within the table
    (structure described below) and ncell is the number of elements
    in this list. Note that a cell may span multiple rows and/or columns,
    thus ncell may be smaller than nrow*ncol. Grid is a two-dimensional
    array of cells within the table; the cell at row i and column
    j is Table.grid[i][j]. A cell that spans multiple rows and/or
    columns will be
    referenced by grid multiple times, however it will only occur
    once in cells. Align gives the alignment specification for the
    entire table, and width gives the requested width as a dimension
    specification. Border, cellspacing and cellpadding give the values
    of the corresponding attributes for the table, and background
    gives the requested
    background for the table. Caption is a linked list of items to
    be displayed as the caption of the table, either above or below
    depending on whether caption_place is ALtop or ALbottom. Most
    of the remaining fields are reserved for use by the caller, except
    tabletok, which is reserved for internal use. The type Lay is
    not defined by the library; the
    caller can provide its own definition. 
    
    
    The Tablecol structure is defined for use by the caller. The library
    ensures that the correct number of these is allocated, but leaves
    them blank. The fields are as follows: 
    
    
    typedef struct Tablecol Tablecol;
 struct Tablecol
 {
 
 };|  |  |  | int    width; Align align;
 Point pos;
 
 | 
 The rows in the table are specified as follows: 
    
    
    typedef struct Tablerow Tablerow;
 struct Tablerow
 {
 
 };|  |  |  | Tablerow*    next; Tablecell* cells;
 int        height;
 int        ascent;
 Align       align;
 Background background;
 Point       pos;
 uchar       flags;
 
 | 
 Next is only used during parsing; it should be ignored by the
    caller. Cells provides a list of all the cells in a row, linked
    through their nextinrow fields (see below). Height, ascent and
    pos are reserved for use by the caller. Align is the alignment
    specification for the row, and background is the background to
    use, if specified. Flags is used by
    the parser; ignore this field. 
    
    
    The individual cells of the table are described as follows: 
    
    
    typedef struct Tablecell Tablecell;
 struct Tablecell
 {
 
 };|  |  |  | Tablecell* next; Tablecell* nextinrow;
 int        cellid;
 Item*       content;
 Lay*       lay;
 int        rowspan;
 int        colspan;
 Align       align;
 uchar       flags;
 Dimen       wspec;
 int        hspec;
 Background background;
 int        minw;
 int        maxw;
 int        ascent;
 int        row;
 int        col;
 Point       pos;
 
 | 
 Next is used to link together the list of all cells within a table
    (Table.cells), whereas nextinrow is used to link together all
    the cells within a single row (Tablerow.cells). Cellid provides
    a serial number for the cell within the table. Content is a linked
    list of the items to be laid out within the cell. Lay is reserved
    for the user to describe how
    these items have been laid out. Rowspan and colspan are the number
    of rows and columns spanned by this cell, respectively. Align
    is the alignment specification for the cell. Flags is some combination
    of TFparsing, TFnowrap and TFisth or’d together. Here TFparsing
    is used internally by the parser, and should be ignored. TFnowrap
    means that the contents of the cell should not be wrapped if they
    don’t fit the available width, rather, the table should be expanded
    if need be (this is set when the nowrap attribute is supplied).
    TFisth means that the cell was created by the <th> element (rather
    than the <td> element), indicating that it is a header cell rather
    than a data cell. Wspec
    provides a suggested width as a dimension specification, and hspec
    provides a suggested height in pixels. Background gives a background
    specification for the individual cell. Minw, maxw, ascent and
    pos are reserved for use by the caller during layout. Row and
    col give the indices of the row and column of the top left-hand
    corner of the cell within
    the table grid.
 
 Client-side Maps    The library builds a list of client-side maps, headed by Docinfo.maps,
    and having the following structure: 
    
    
    typedef struct Map Map;
 struct Map
 {
 
 };|  |  |  | Map*    next; Rune* name;
 Area* areas;
 
 | 
 Next points to the next element in the list, name is the name
    of the map (use to bind it to an image), and areas is a list of
    the areas within the image that comprise the map, using the following
    structure: 
    
    
    typedef struct Area Area;
 struct Area
 {
 
 };|  |  |  | Area*    next; int     shape;
 Rune*    href;
 int     target;
 Dimen* coords;
 int     ncoords;
 
 | 
 Next points to the next element in the map’s list of areas. Shape
    describes the shape of the area, and is one of SHrect, SHcircle
    or SHpoly. Href is the URL associated with this area in its role
    as a hypertext link, and target is the target frame it should
    be loaded in. Coords is an array of coordinates for the shape,
    and ncoords is the size of
    this array (number of elements).
 
 Frames     If the Docinfo.kidinfo field is set, the document is a frameset.
    In this case, it is typical for parsehtml to return nil, as a
    document which is a frameset should have no actual items that
    need to be laid out (such will appear only in subsidiary documents).
    It is possible that items will be returned by a malformed document;
    the caller should check for this
    and free any such items. 
    
    
    The Kidinfo structure itself reflects the fact that framesets
    can be nested within a document. If is defined as follows: 
    
    
    typedef struct Kidinfo Kidinfo;
 struct Kidinfo
 {
 
 };|  |  |  | Kidinfo* next; int       isframeset;
 // fields for "frame"
 Rune*     src;
 Rune*     name;
 int       marginw;
 int       marginh;
 int       framebd;
 int       flags;
 // fields for "frameset"
 Dimen*    rows;
 int       nrows;
 Dimen*    cols;
 int       ncols;
 Kidinfo* kidinfos;
 Kidinfo* nextframeset;
 
 | 
 Next is only used if this structure is part of a containing frameset;
    it points to the next element in the list of children of that
    frameset. Isframeset is set when this structure represents a frameset;
    if clear, it is an individual frame. 
    
    
    Some fields are used only for framesets. Rows is an array of dimension
    specifications for rows in the frameset, and nrows is the length
    of this array. Cols is the corresponding array for columns, of
    length ncols. Kidinfos points to a list of components contained
    within this frameset, each of which may be a frameset or a frame.
    Nextframeset is
    only used during parsing, and should be ignored. 
    
    
    The remaining fields are used if the structure describes a frame,
    not a frameset. Src provides the URL for the document that should
    be initially loaded into this frame. Note that this may be a relative
    URL, in which case it should be interpretted using the containing
    document’s URL as the base. Name gives the name of the frame,
    typically supplied via a
    name attribute in the HTML. If no name was given, the library
    allocates one. Marginw, marginh and framebd are the values of
    the marginwidth, marginheight and frameborder attributes, respectively.
    Flags can contain some combination of the following: FRnoresize
    (the frame had the noresize attribute set, and the user should
    not be allowed to
    resize it), FRnoscroll (the frame should not have any scroll bars),
    FRhscroll (the frame should have a horizontal scroll bar), FRvscroll
    (the frame should have a vertical scroll bar), FRhscrollauto (the
    frame should be automatically given a horizontal scroll bar if
    its contents would not otherwise fit), and FRvscrollauto (the
    frame gets a vertical
    scrollbar only if required).
 
 | 
 SOURCE     
 SEE ALSO    
 |  |  |  | fmt(1) 
    
    
    W3C World Wide Web Consortium, “HTML 4.01 Specification”. 
 | 
 BUGS     
 |  |  |  | The entire HTML document must be loaded into memory before any
    of it can be parsed. 
 | 
 |  |