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Edit File: log.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE logmap [
<!ELEMENT logmap (log)+>
<!ELEMENT log (#PCDATA)>
<!ATTLIST log events CDATA #IMPLIED>
<!ATTLIST log output CDATA #IMPLIED>
<!ATTLIST log filename CDATA #IMPLIED>
<!ATTLIST log generations CDATA #IMPLIED>
<!ATTLIST log limit CDATA #IMPLIED>
<!ATTLIST log format CDATA #IMPLIED>
]>
<!--
  Configure ImageMagick logger.

Choose from one or more these events separated by a comma:
    all
    accelerate
    annotate
    blob
    cache
    coder
    command
    configure
    deprecate
    draw
    exception
    locale
    module
    none
    pixel
    policy
    resource
    trace
    transform
    user
    wand
    x11

Choose one output handler:
    console
    debug
    event
    file
    none
    stderr
    stdout

When output is to a file, specify the filename.  Embed %g in the filename to
  support log generations.  Generations is the number of log files to retain.
  Limit is the number of logging events before generating a new log generation.

The format of the log is defined by embedding special format characters:

%c   client
    %d   domain
    %e   event
    %f   function
    %g   generation
    %i   thread id
    %l   line
    %m   module
    %n   log name
    %p   process id
    %r   real CPU time
    %t   wall clock time
    %u   user CPU time
    %v   version
    %%   percent sign
    \n   newline
    \r   carriage return
    xml
-->
<logmap>
  <log events="None"/>
  <log output="console"/>
  <log filename="Magick-%g.log"/>
  <log generations="3"/>
  <log limit="2000"/>
  <log format="%t %r %u %v %d %c[%p]: %m/%f/%l/%d\n  %e"/>
</logmap>