xcb_intern_atom_reply3

Usage

Request arguments

conn

The XCB connection to X11.

only_if_exists

Return a valid atom id only if the atom already exists.

name_len

The length of the following name.

name

The name of the atom.

Reply fields

response_type

The type of this reply, in this case XCB_INTERN_ATOM. 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).

atom

TODO: NOT YET DOCUMENTED.

Overview

Retrieves the identifier (xcb_atom_t TODO) for the atom with the specified name. Atoms are used in protocols like EWMH, for example to store window titles (_NET_WM_NAME atom) as property of a window.

If only_if_exists is 0, the atom will be created if it does not already exist. If only_if_exists is 1, XCB_ATOM_NONE will be returned if the atom does not yet exist.

Return value

Returns an xcb_intern_atom_cookie_t. Errors have to be handled when calling the reply function xcb_intern_atom_reply.

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

Errors

xcb_alloc_error_t

TODO: reasons?

xcb_value_error_t

A value other than 0 or 1 was specified for only_if_exists.

Examples

/*
 * Resolves the _NET_WM_NAME atom.
 *
 */
void my_example(xcb_connection_t *c) {
    xcb_intern_atom_cookie_t cookie;
    xcb_intern_atom_reply_t *reply;
    cookie = xcb_intern_atom(c, 0, strlen("_NET_WM_NAME"), "_NET_WM_NAME");
    /* ... do other work here if possible ... */
    if ((reply = xcb_intern_atom_reply(c, cookie, NULL))) {
        printf("The _NET_WM_NAME atom has ID %u0, reply->atom);
        free(reply);
    }
}