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The "FUQ" page has been changed by RandallLeeds:
http://wiki.apache.org/couchdb/FUQ?action=diff&rev1=3&rev2=4

Comment:
More information about Erlang backtraces.

  
  == Log Files ==
   1. Those Erlang messages in the log are pretty confusing. What gives?
+    While the Erlang messages in the log can be confusing to someone 
unfamiliar with Erlang, with practice they become very helpful. The CouchDB 
developers do try to catch and log messages that might be useful to a system 
administrator in a friendly format, but occassionally a bug or otherwise 
unexpected behavior manifests itself in more verbose dumps of Erlang server 
state. These messages can be very useful to CouchDB developers. If you find 
many confusing messages in your log, feel free to inquire about them. If they 
are expected, devs can work to ensure that the message is more cleanly 
formatted. Otherwise, the messages may indicate a bug in the code.
-    Erlang kindly provides us with a stack trace. In many cases, this is 
enough to identify the problem. For example, OS errors are reported as tagged 
tuples {{{{error,enospc}}}} or {{{{error,enoacces}}}} which respectively is 
"You ran out of disk space", and "CouchDB doesn't have permission to access 
that resource". Most of these errors are derived from C used to build the 
Erlang VM and are documented in {{{errno.h}}} and related header files. 
[[http://www.ibm.com/developerworks/aix/library/au-errnovariable/|IBM]] 
provides a good introduction to these, and the relevant 
[[http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html|POSIX]] 
and [[http://www.gnu.org/s/hello/manual/libc/Error-Codes.html|GNU]] and 
[[http://msdn.microsoft.com/en-us/library/5814770t.aspx|Microsoft Windows]] 
standards will cover most cases.
+    In many cases, this is enough to identify the problem. For example, OS 
errors are reported as tagged tuples {{{{error,enospc}}}} or 
{{{{error,enoacces}}}} which respectively is "You ran out of disk space", and 
"CouchDB doesn't have permission to access that resource". Most of these errors 
are derived from C used to build the Erlang VM and are documented in 
{{{errno.h}}} and related header files. 
[[http://www.ibm.com/developerworks/aix/library/au-errnovariable/|IBM]] 
provides a good introduction to these, and the relevant 
[[http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/errno.h.html|POSIX]] 
and [[http://www.gnu.org/s/hello/manual/libc/Error-Codes.html|GNU]] and 
[[http://msdn.microsoft.com/en-us/library/5814770t.aspx|Microsoft Windows]] 
standards will cover most cases.
  

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