XLOCK(1) USER COMMANDS XLOCK(1) NAME xlock - Locks the local X display till a password is entered. SYNOPSIS xlock [ -display _d_s_p ] [ -mode _m_o_d_e ] [ -time _t_i_m_e_o_u_t ] [ -count _n ] [ -font _f_o_n_t_n_a_m_e ] [ -nice _n_i_c_e_l_e_v_e_l ] [ -mono ] [ -saver ] [ -root ] [ -v ] DESCRIPTION xlock locks the X server till the user enters their password at the keyboard. While xlock is running, all new server connections are refused. The screen saver is disabled. The mouse cursor is turned off. The screen is blanked and a changing pattern is put on the screen. The pattern changes after _t_i_m_e_o_u_t seconds. If a key or a mouse button is pressed then the user is prompted for the password of the user who started xlock. If the correct password is typed, then the screen is unlocked and the X server is restored. When typing the password, characters are echoed to the screen as question marks (?), and Control-U and Control-H are active as kill and erase respectively. To return to the locked screen, click in the small icon version of the changing pattern. OPTIONS -display dsp The _d_i_s_p_l_a_y option sets the X11 display to lock. xlock will not allow one to lock another server's displays thus only unix:server.screen, localhost:server.screen, and :server.screen are allowed for _d_s_p. Where _s_e_r_v_e_r is which X11 server socket to connect to and _s_c_r_e_e_n is which head to display the pattern on. -mode modename As of this writing there are three display modes sup- ported. hop Hop mode shows the "real plane fractals" from the September 1986 issue of Scientific American. life Life mode shows Conway's game of life. qix Qix mode shows the spinning lines similar to the old video game by the same name. -time timeout The _t_i_m_e option sets the number of seconds that each X11R4 Last change: 20 Sep 1989 1 XLOCK(1) USER COMMANDS XLOCK(1) unique fractal will remain on the screen before being replaced by the next one to _t_i_m_e_o_u_t. -count n The _c_o_u_n_t option sets the speed at which a mode will operate. The different modes interpret this value dif- ferently. For 'hop' and 'qix' this sets the number of pixels and lines respectively to draw in each color. These patterns are calculated in batches of _n objects, then sent to the server in a single color. Faster machines, expecially machines with floating point hardware can set this to a higher number and still have fast changing patterns. The 'life' mode, in contrast interprets this number as the number of milliseconds to delay after each generation of the "critters". A low number here makes the pattern change rapidly, where 1000 means wait a second between generations. -font fontname The _f_o_n_t option sets the font to be used on the prompt screen. -nice nicelevel The _n_i_c_e option sets system nicelevel of the xlock pro- cess to _n_i_c_e_l_e_v_e_l . -mono The _m_o_n_o option causes xlock to display monochrome, (black and white) pixels rather than the default colored ones on color displays. -saver The _s_a_v_e_r option causes xlock to only draw the patterns and not lock the display. A keypress or a mouse click will terminate the screen saver. -root The _r_o_o_t option allows the root password to unlock the server as well as the user who started xlock. -v Verbose mode, tells what options it is going to use. BUGS "kill -KILL xlock " causes server to be unusable, since xlock has removed all hosts (including localhost) from the access control list to lock out all new X clients, and SIG- KILL cannot be caught by any program, xlock will terminate before restoring the access control list. This will leave the X server in a state where "_y_o_u _c_a_n _n_o _l_o_n_g_e_r _c_o_n_n_e_c_t _t_o _t_h_a_t _s_e_r_v_e_r, _a_n_d _t_h_i_s _o_p_e_r_a_- _t_i_o_n _c_a_n_n_o_t _b_e _r_e_v_e_r_s_e_d _s_h_o_r_t _o_f _r_e_s_e_t_t_i_n_g _t_h_e _s_e_r_v_e_r." X11R4 Last change: 20 Sep 1989 2 XLOCK(1) USER COMMANDS XLOCK(1) -From the X11R2 Xlib Documentation page 140. SEE ALSO X(1), Xlib Documentation. AUTHOR Patrick J. Naughton (naughton@sun.com) Window Systems Group Sun Microsystems, Inc. Mountain View, CA 94043 415/336-1080 COPYRIGHT Copyright (c) 1988-89 by Patrick J. Naughton and Sun Microsystems, Inc. Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting docu- mentation. CONTRIBUTORS milliken@heron.bbn.com karlton@wsl.dec.com dana@thumper.bellcore.com vesper@3d.dec.com flar@sun.com X11R4 Last change: 20 Sep 1989 3