xcb_alloc_color

Section: XCB Requests (3)
Updated: libxcb 1.13.1
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NAME

xcb_alloc_color - Allocate a color

SYNOPSIS

#include <xcb/xproto.h>

Request function

: xcb_alloc_color_cookie_t xcb_alloc_color(xcb_connection_t *conn, xcb_colormap_t cmap, uint16_t red, uint16_t green, uint16_t blue);

Reply datastructure


typedef struct xcb_alloc_color_reply_t {
    uint8_t  response_type;
    uint8_t  pad0;
    uint16_t sequence;
    uint32_t length;
    uint16_t red;
    uint16_t green;
    uint16_t blue;
    uint8_t  pad1[2];
    uint32_t pixel;
} xcb_alloc_color_reply_t;

Reply function

: xcb_alloc_color_reply_t *xcb_alloc_color_reply(xcb_connection_t *conn, xcb_alloc_color_cookie_t cookie, xcb_generic_error_t **e);

REQUEST ARGUMENTS

conn: The XCB connection to X11.
cmap: TODO
red: The red value of your color.
green: The green value of your color.
blue: The blue value of your color.

REPLY FIELDS

response_type: The type of this reply, in this case XCB_ALLOC_COLOR. This field is also present in the xcb_generic_reply_t and can be used to tell replies apart from each other.
sequence: The sequence number of the last request processed by the X11 server.
length: The length of the reply, in words (a word is 4 bytes).
red: TODO: NOT YET DOCUMENTED.
green: TODO: NOT YET DOCUMENTED.
blue: TODO: NOT YET DOCUMENTED.
pixel: TODO: NOT YET DOCUMENTED.

DESCRIPTION

Allocates a read-only colormap entry corresponding to the closest RGB value supported by the hardware. If you are using TrueColor, you can take a shortcut and directly calculate the color pixel value to avoid the round trip. But, for example, on 16-bit color setups (VNC), you can easily get the closest supported RGB value to the RGB value you are specifying.

RETURN VALUE

Returns an xcb_alloc_color_cookie_t. Errors have to be handled when calling the reply function xcb_alloc_color_reply.

If you want to handle errors in the event loop instead, use xcb_alloc_color_unchecked. See xcb-requests(3) for details.

ERRORS

xcb_colormap_error_t: The specified colormap cmap does not exist.

AUTHOR

Generated from xproto.xml. Contact xcb@lists.freedesktop.org for corrections and improvements.