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    EasyRequestArgs -- Easy alternative to AutoRequest(). (V36)
    EasyRequest -- Varargs stub for EasyRequestArgs(). (V36)

    num = EasyRequestArgs( Window, easyStruct, IDCMP_ptr, ArgList )
    D0                     A0      A1          A2         A3

    LONG EasyRequestArgs( struct Window *, struct EasyStruct *,
            ULONG *, APTR );

    num = EasyRequest( Window, easyStruct, IDCMP_ptr, Arg1, Arg2, ... )

    LONG EasyRequest( struct Window *, struct EasyStruct *,
            ULONG *, APTR, ... );

    ( from intuition.h )
    struct EasyStruct {
        ULONG       es_StructSize;
        ULONG       es_Flags;
        UBYTE       *es_Title;
        UBYTE       *es_TextFormat;
        UBYTE       *es_GadgetFormat;

    This function provides a simpler method of using a 'System
    Requester' than provided by AutoRequest().  It performs layout
    and size calculations sensitive to the current font and screen

    It provides for the descriptive 'body' text and the gadget
    text to be constructed from 'printf' style format strings.

    It also provides a general way for the requester to be
    sensitive to particular IDCMP messages.

    The first function listed is the actual Intuition library
    function.  It is passed the arguments for the formatting
    operations as a pointer to the first argument.

    The second function uses a C-style variable number of argument
    (varargs) calling convention.  It should be implemented as
    a call to the first function, and might be supplied by your
    compiler vendor, in amiga.lib, or using the first example below,
    for most C compilers.

    NOTE: The formatting is done by exec.library/RawDoFmt(), so
    be aware that to display a 32-bit integer argument, for
    example, you must say "%ld", not "%d", since RawDoFmt() is

    NOTE: This function switches the processor stack to ensure
    sufficient stack space for the function to complete.

    /* varargs interface works for most C compilers */
    EasyRequest( w, es, ip, arg1 )
    struct Window   *w;
    struct EasyStruct *es;
    ULONG             *ip;
    int               arg1;
        return ( EasyRequestArgs( w, es, ip, &arg1 ) );


    /* typical use */
    struct EasyStruct volumeES = {
        sizeof (struct EasyStruct),
        "Volume Request",
        "Please insert volume %s in any drive.",
    #define CANCEL  (0)

    Volume  *
    getVolume( volname )
    UBYTE   *volname;
        Volume      *vptr;
        Volume      *findVolume();
        UWORD       reply;
        ULONG       iflags;

        iflags = IDCMP_DISKINSERTED;

    while ( ((vptr = findVolume( volname )) == NULL) &&
     (EasyRequest( w, &volumeES, &iflags, volname ) != CANCEL) )
            /* loop */ ;

        /* note that in some circumstances, you will have to
           re-initialize the value of 'iflags'.  Here, it
           is either unchanged, or returned as the single
           IDCMPFlag value IDCMP_DISKINSERTED.  If you combine
           multiple  IDCMPFlag values in 'iflags,' only
           one will be returned, so you must reinitialize
           'iflags' to be the combination.
        return ( vptr );

    Window = Reference window pointer, determines the screen and
        title of the requester window.  This can be NULL, which
        means the requester is to appear on the Workbench screen,
        or default public screen, if defined.
    IDCMP_ptr = Pointer to IDCMP flags that you want to terminate
            the requester.  This pointer may be NULL.
    easyStruct = Pointer to EasyStruct structure with fields
            interpreted as follows:

    es_StructSize = sizeof (struct EasyStruct), for future extension.
    es_Flags = 0 for now, in the future may specify other options.
    es_Title = Title of system requester window.  If this is NULL,
        the title will be taken to be the same as the title of 'Window',
        if provided, or else "System Request."
    es_TextFormat = Format string, a la RawDoFmt(), for message in
        requester body.  Lines are separated by 'n'.  Formatting
        '%' functions are supported exactly as in RawDoFmt().
    es_GadgetFormat = Format string for gadgets.  Text for separate
        gadgets is separated by '|'.  Format functions are supported.
        You MUST specify at least one gadget.

    Args = Arguments for format commands.   Arguments for
        GadFmt follow arguments for TextFmt.

    0, 1, ..., N = Successive GadgetID values, for the gadgets
        you specify for the requester.  NOTE: The numbering
        from left to right is actually: 1, 2, ..., N, 0.
        This is for compatibility with AutoRequests which has
        FALSE for the rightmost gadget.

    -1 = Means that one of the caller-supplied IDCMPFlags occurred.
        The IDCMPFlag value is in the longword pointed to by IDCMP_ptr.

    When DOS brings up EasyRequests() on your process (eg.
    "Please insert volume XXX in any drive", they normally come
    up on the default public screen, which is usually the Workbench
    screen.  If you set your Process pr_WindowPtr field to point to
    one of your windows, then DOS will bring its requesters up on the
    same screen as that window.  A pr_WindowPtr of -1 prevents
    requesters from coming up at all.
    (Some FileSystem requesters cannot be redirected or supressed).

    Does not fall back to a recoverable alert if the requester
     cannot be created.

    Does not handle case when gadgets don't fit or window title
    is too long, although it does trim trailing spaces from the
    title for calculating dimensions.

    Possible enhancements include: centering of text, size-sensitive
    layout,  window-relative requester, vertical gadget layout,
    window placement, more keyboard shortcuts.

    We also reserve the use of the newline character 'n' in
    gadget format strings for future use as a line separator.

    exec.library/RawDoFmt(), BuildEasyRequestArgs(), SysReqHandler(),
    AutoRequest(), BuildSysRequest()

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