[=][<_w_i_d_t_h>{xX}<_h_e_i_g_h_t>][{+-}<_x_o_f_f_s_e_t>{+-}<_y_o_f_f_s_e_t>]
The fields map into the arguments associated with this function. (Items enclosed in <> are integers, items in [] are optional, and items enclosed in {} indicate ``choose one of.'' Note that the brackets should not appear in the actual string.) If the string is not in the Host Portable Character Encoding, the result is implementation-dependent.
The _X_P_a_r_s_e_G_e_o_m_e_t_r_y function returns a bitmask that indicates which of the four values (width, height, xoffset, and yoffset) were actually found in the string and whether the x and y values are negative. By convention, -0 is not equal to +0, because the user needs to be able to say ``position the window relative to the right or bottom edge.'' For each value found, the corresponding argument is updated. For each value not found, the argument is left unchanged. The bits are represented by _X_V_a_l_u_e, _Y_V_a_l_u_e, _W_i_d_t_h_V_a_l_u_e, _H_e_i_g_h_t_V_a_l_u_e, _X_N_e_g_a_t_i_v_e, or _Y_N_e_g_a_t_i_v_e and are defined in <_X_1_1_/_X_u_t_i_l_._h>. They will be set whenever one of the values is defined or one of the signs is set.
If the function returns either the _X_V_a_l_u_e or _Y_V_a_l_u_e flag, you should place the window at the requested position.
The _X_W_M_G_e_o_m_e_t_r_y function combines any geometry information (given in the format used by _X_P_a_r_s_e_G_e_o_m_e_t_r_y) specified by the user and by the calling program with size hints (usually the ones to be stored in WM_NORMAL_HINTS) and returns the position, size, and gravity (_N_o_r_t_h_W_e_s_t_G_r_a_v_i_t_y, _N_o_r_t_h_E_a_s_t_G_r_a_v_i_t_y, _S_o_u_t_h_E_a_s_t_G_r_a_v_i_t_y, or _S_o_u_t_h_W_e_s_t_G_r_a_v_i_t_y) that describe the window. If the base size is not set in the _X_S_i_z_e_H_i_n_t_s structure, the minimum size is used if set. Otherwise, a base size of zero is assumed. If no minimum size is set in the hints structure, the base size is used. A mask (in the form returned by _X_P_a_r_s_e_G_e_o_m_e_t_r_y) that describes which values came from the user specification and whether or not the position coordinates are relative to the right and bottom edges is returned. Note that these coordinates will have already been accounted for in the x_return and y_return values.
Note that invalid geometry specifications can cause a width or height of zero to be returned. The caller may pass the address of the hints win_gravity field as gravity_return to update the hints directly.