NAME

XtDisplayInitialize, XtOpenDisplay, XtDatabase, XtScreenDatabase, XtCloseDisplay - initialize, open, or close a display

SYNTAX

void XtDisplayInitialize(XtAppContext _a_p_p___c_o_n_t_e_x_t, Display *_d_i_s_p_l_a_y, String _a_p_p_l_i_c_a_t_i_o_n___n_a_m_e, String _a_p_p_l_i_c_a_t_i_o_n___c_l_a_s_s, XrmOptionDescRec *_o_p_t_i_o_n_s, Cardinal _n_u_m___o_p_t_i_o_n_s, int *_a_r_g_c, String *_a_r_g_v); Display *XtOpenDisplay(XtAppContext _a_p_p___c_o_n_t_e_x_t, String _d_i_s_p_l_a_y___s_t_r_i_n_g, String _a_p_p_l_i_c_a_t_i_o_n___n_a_m_e, String _a_p_p_l_i_c_a_t_i_o_n___c_l_a_s_s, XrmOptionDescRec *_o_p_t_i_o_n_s, Cardinal _n_u_m___o_p_t_i_o_n_s, int *_a_r_g_c, String *_a_r_g_v); void XtCloseDisplay(Display *_d_i_s_p_l_a_y); XrmDatabase XtDatabase(Display *_d_i_s_p_l_a_y); XrmDatabase XtScreenDatabase(Screen* _s_c_r_e_e_n);

ARGUMENTS

_a_r_g_c Specifies a pointer to the number of command line parameters.
_a_r_g_v Specifies the command line parameters.
_a_p_p___c_o_n_t_e_x_t Specifies the application context.
_a_p_p_l_i_c_a_t_i_o_n___c_l_a_s_s Specifies the class name of this application, which usually is the generic name for all instances of this application.
_a_p_p_l_i_c_a_t_i_o_n___n_a_m_e Specifies the name of the application instance.
_d_i_s_p_l_a_y Specifies the display.
Note that a display can be in at most one application context.
_n_u_m___o_p_t_i_o_n_s Specifies the number of entries in the options list.
_o_p_t_i_o_n_s Specifies how to parse the command line for any application-specific resources.
The options argument is passed as a parameter to _X_r_m_P_a_r_s_e_C_o_m_m_a_n_d. For further information, see _X_l_i_b _- _C _L_a_n_g_u_a_g_e _X _I_n_t_e_r_f_a_c_e.
_s_c_r_e_e_n Specifies the screen whose resource database is to be returned.

DESCRIPTION

The _X_t_D_i_s_p_l_a_y_I_n_i_t_i_a_l_i_z_e function builds the resource database, calls the Xlib _X_r_m_P_a_r_s_e_C_o_m_m_a_n_d function to parse the command line, and performs other per display initialization. After _X_r_m_P_a_r_s_e_C_o_m_m_a_n_d has been called, argc and argv contain only those parameters that were not in the standard option table or in the table specified by the options argument. If the modified argc is not zero, most applications simply print out the modified argv along with a message listing the allowable options. On UNIX-based systems, the application name is usually the final component of argv[0]. If the synchronize resource is _T_r_u_e for the specified application, _X_t_D_i_s_p_l_a_y_I_n_i_t_i_a_l_i_z_e calls the Xlib _X_S_y_n_c_h_r_o_n_i_z_e function to put Xlib into synchronous mode for this display connection. If the reverseVideo resource is _T_r_u_e, the Intrinsics exchange _X_t_D_e_f_a_u_l_t_F_o_r_e_g_r_o_u_n_d and _X_t_D_e_f_a_u_l_t_B_a_c_k_g_r_o_u_n_d for widgets created on this display. (See Section 9.6.1).

The _X_t_O_p_e_n_D_i_s_p_l_a_y function calls _X_O_p_e_n_D_i_s_p_l_a_y the specified display name. If display_string is NULL, _X_t_O_p_e_n_D_i_s_p_l_a_y uses the current value of the -display option specified in argv and if no display is specified in argv, uses the user's default display (on UNIX-based systems, this is the value of the DISPLAY environment variable).

If this succeeds, it then calls _X_t_D_i_s_p_l_a_y_I_n_i_t_i_a_l_i_z_e and pass it the opened display and the value of the -name option specified in argv as the application name. If no name option is specified, it uses the application name passed to _X_t_O_p_e_n_D_i_s_p_l_a_y. If the application name is NULL, it uses the last component of argv[0]. _X_t_O_p_e_n_D_i_s_p_l_a_y returns the newly opened display or NULL if it failed.

_X_t_O_p_e_n_D_i_s_p_l_a_y is provided as a convenience to the application programmer.

The _X_t_C_l_o_s_e_D_i_s_p_l_a_y function closes the specified display as soon as it is safe to do so. If called from within an event dispatch (for example, a callback procedure), _X_t_C_l_o_s_e_D_i_s_p_l_a_y does not close the display until the dispatch is complete. Note that applications need only call _X_t_C_l_o_s_e_D_i_s_p_l_a_y if they are to continue executing after closing the display; otherwise, they should call _X_t_D_e_s_t_r_o_y_A_p_p_l_i_c_a_t_i_o_n_C_o_n_t_e_x_t or just exit.

The _X_t_D_a_t_a_b_a_s_e function returns the fully merged resource database that was built by _X_t_D_i_s_p_l_a_y_I_n_i_t_i_a_l_i_z_e associated with the display that was passed in. If this display has not been initialized by _X_t_D_i_s_p_l_a_y_I_n_i_t_i_a_l_i_z_e, the results are not defined.

The _X_t_S_c_r_e_e_n_D_a_t_a_b_a_s_e function returns the fully merged resource database associated with the specified screen. If the _s_c_r_e_e_n does not belong to a _D_i_s_p_l_a_y initialized by _X_t_D_i_s_p_l_a_y_I_n_i_t_i_a_l_i_z_e, the results are undefined.

SEE ALSO

XtAppCreateShell(3Xt), XtCreateApplicationContext(3Xt)
_X _T_o_o_l_k_i_t _I_n_t_r_i_n_s_i_c_s _- _C _L_a_n_g_u_a_g_e _I_n_t_e_r_f_a_c_e
_X_l_i_b _- _C _L_a_n_g_u_a_g_e _X _I_n_t_e_r_f_a_c_e