Question: I'm running ...[xxx-system]... with Xserver and keep having problems 
launching a display monitor when executing d.mon (from x0 to x6). Here 
is the error message: 
X Error of failed request:  BadMatch (invalid parameter attributes)
  Major opcode of failed request:  78 (X_CreateColormap)
  Serial number of failed request:  270
  Current serial number in output stream:  271

Answer: You are using a different colormode between GRASS and
your XServer. Getting this error message you are using a 24bit XServer,
but GRASS is configured for 8bit.

 1. login: root
 2. cd /usr/local/grass42/driver/
 3. ls -la

  It will look like this:
    drwxrwxrwx   2 neteler  user         512 Jun 25 17:15 .
    drwxr-xr-x  14 neteler  user         512 Jul 10 11:25 ..
    -rwxrwxr-x   1 neteler  user       96364 Jun 25 17:15 CELL
    lrwxrwxrwx   1 root     other          9 Jun 15 15:21 XDRIVER -> XDRIVER_8
    -rwxr-xr-x   1 neteler  user       41880 Apr  2 10:59 XDRIVER_24bit
    -rwxr-xr-x   1 neteler  user       41660 Apr  2 10:59 XDRIVER_8bit

 4. Change the link to the correct XDRIVER
     rm XDRIVER
     ln -s XDRIVER_24bit XDRIVER

 Now GRASS is configured for 24bit and you should be able to launch 
 the GRASS monitors.

Markus Neteler    16th July 1998

Go back to GRASS GIS FAQ...