


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



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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."



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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


























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