OA15752: XVFB FAILS TO START AND PRODUCES GARBAGE MESSAGES

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Using the Xvfb command on OMVS, fails to start Xvfb and the
  messages are garbled. This is because the messages are being
  issued in ASCII.  If the output is redirected to a file and
  then translated, the translated messages are (one or more
  messages may be issued) :-
  
  XVFB0110: Couldn't open RGB_DB '/usr/local/ascii/lib/X11/rgb'
  XVFB0113: Fatal server error:
  XVFB0163: no screens found
  
  XVFB0110: Couldn't open RGB_DB '/usr/local/ascii/lib/X11/rgb'
  error opening security policy file
  /usr/local/ascii/lib/X11/xserver/SecurityPoli
  XVFB0106: failed to set default font path
  '/usr/local/ascii/lib/X11/fonts/misc/,
  Fatal server error:
  XVFB0171: could not open default font 'fixed'
  
  The errors occur as some of the font, rgb and security policy
  files are missing.
  

Local fix

• Until a PTF becomes available, the necessary files and
  instructions on how to use them can be obtained by contacting
  IBM support
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users of the Xvfb                            *
  *                 application (Ported Tools for z/OS: Xvfb     *
  *                 Feature).                                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: When Xvfb is attempted to be started,   *
  *                      it fails and messages are displayed in  *
  *                      unreadable characters (the output       *
  *                      messages are garbled).  They are in     *
  *                      fact being displayed in ASCII text and  *
  *                      so are not readable on an EBCDIC        *
  *                      terminal.                               *
  *                                                              *
  *                      If the messages are captured and        *
  *                      translated from EBCDIC to ASCII, they   *
  *                      are one or more of the following        *
  *                      (depending on what options and          *
  *                      environment is in place):               *
  *                                                              *
  *                       XVFB0110: Couldn't open RGB_DB ...     *
  *                       XVFB0113: Fatal server error:          *
  *                       XVFB0163: no screens found             *
  *                       XVFB0106: failed to set default font   *
  *                       path ...                               *
  *                       Fatal server error:                    *
  *                       XVFB0171: could not open default font  *
  *                       'fixed'                                *
  *                                                              *
  *                      In general, users may see errors        *
  *                      regarding invalid font files or paths,  *
  *                      invalid RGB file, or invalid            *
  *                      security policy file.                   *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The problems that are being experienced
  are due to several factors:
  
  * Required environment variables not
    documented in IBM documentation
  * font files required
  * RGB files required
  * Security Policy file required
  
  No changes are required to the
  installed Xvfb module.
  
  The Xvfb application was compiled using
  "Enhanced Ascii" support meaning that
  it automatically converts input from
  ASCII to EBCDIC and output from EBCDIC
  to ASCII.  To correctly support the
  display of messages and to recognize
  the font files which are tagged as
  ASCII, the following environment
  variables must be defined:
  
  _BPXK_AUTOCVT=ON
  _CEE_RUNOPTS="FILETAG(AUTOCVT,AUTOTAG)"
  export _BPXK_AUTOCVT _CEE_RUNOPTS
  export _TAG_REDIR_IN=TXT
  export _TAG_REDIR_OUT=TXT
  export _TAG_REDIR_ERR=TXT
  
  A sample "startXvfb.sh" shell script
  has been provided to define these.
  
  Additionally, the Xvfb application must
  have access to a minimum set of default
  fonts.   While these can be remotely
  accessed via a font server, it is
  helpful to have them provided on the
  same system.
  
  Finally, a Security Policy file is
  required as input to Xvfb.
  
  The user might be able to determine how
  to access the fonts and create the
  Security Policy file, but it is not
  well documented and the Enhanced Ascii
  environment was not documented at all.
  
  So, in summary, it would be very
  difficult, if not impossible, for
  the user to figure out how to
  successfully start Xvfb without more
  guidance and sample files.
  

Problem conclusion

• This fix provides a set of default fonts,  a sample
  Security Policy file, and a startXvfb.sh shell script which
  can be used to correctly initialize the Xvfb environment and
  start the Xvfb application.  It can be used as a sample
  and modified further according to the users needs.
  
  These files are installed into a "samples" sub-directory of
  the directory Xvfb is normally installed into.  The following
  shows the original Xvfb directory and new sample files and
  font directories (actual font files too numerous to show):
  
  Original Xvfb File:
  /usr/lpp/tcpip/bin/X11/Xvfb    # Xvfb application
  
  New Sample Files:
  
  /usr/lpp/tcpip/bin/X11/samples/SecurityPolicy
  /usr/lpp/tcpip/bin/X11/samples/startXvfb.sh
  /usr/lpp/tcpip/bin/X11/samples/rgb.txt
  
  New Font Files:
  
  /usr/lpp/tcpip/bin/X11/samples/fonts/100dpi/
  /usr/lpp/tcpip/bin/X11/samples/fonts/75dpi/
  /usr/lpp/tcpip/bin/X11/samples/fonts/Speedo/
  /usr/lpp/tcpip/bin/X11/samples/fonts/Type1/
  /usr/lpp/tcpip/bin/X11/samples/fonts/misc/
  
  After installing the fix, the user can start Xvfb with
  the startXvfb.sh script.  This script references the same
  files and fonts.  It starts Xvfb with a default set of
  options.  It can be used as an example and modified to
  start Xvfb with different options.
  
  Here is an example of running startXvfb.sh:
  
    >  cd /usr/lpp/tcpip/bin/X11/samples/
    >  ./startXvfb.sh
    Starting Xvfb using server/display :8
    Xvfb will be run in the background.
    Run "ps -ef | grep Xvfb" to see process ID.
    Should you see the message:
        XVFB0178: Failed to establish all listening sockets
    specify a different server/display number.
  
  By default, startXvfb.sh will start Xvfb and initialize the
  Server/Display number to be 8.  The port that Xvfb will be
  defined at is 6000 plus the server number.  To avoid conflicts
  with other applications that are defined at 6000, we will set
  default server number to be 8.  The "netstat -o" can be used to
  determine which ports have been predefined to other
  applications.
  
  The server/display number can be changed by specifying a
  different number as an argument to startXvfb.sh.   This is
  the only option supported by startXvfb.sh.  For example, to
  start it at number 1:
  
    >  cd /usr/lpp/tcpip/bin/X11/samples/
    >  ./startXvfb.sh  1
    Starting Xvfb using server/display :1
    Xvfb will be run in the background.
    Run "ps -ef | grep Xvfb" to see process ID.
    Should you see the message:
        XVFB0178: Failed to establish all listening sockets
    specify a different server/display number.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UA32671

Modules/Macros

•    FNUPFONT FNUSPAXF
  

Fix information

• Fixed component name

  XVFB FOR Z/OS

• Fixed component ID

  5655M2302

Applicable component levels

• R110 PSY UA32671

     UP07/02/28 P F702

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.