[[!comment format=mdwn
 username="https://www.google.com/accounts/o8/id?id=AItOawnWvnTWY6LrcPB4BzYEBn5mRTpNhg5EtEg"
 nickname="Bence"
 subject="checkpresent success and failure"
 date="2013-07-31T13:06:21Z"
 content="""
What value should be returned in the \"checkpresent-hook\" to signal that the given file does not exist in the given backend? 

Should the called hook process return an exit code less or greater then zero? In this case the following is displayed: 
>(user error (sh [\"-c\",\"name_of_the_process\"] exited 1)) failed

This tells that the process failed (no internet connection or something that prevents the process from doing its job) and not that result is false, which would mean the file/entry does not exist in the given backend.
If the return code is zero the file is treated as existing file/entry (no matter what I write to stderr).

Also I think, the \"checkpresent\" block misses the ending ;; in the example.

Here is my work-in-progress hook: https://gist.github.com/parhuzamos/31bf4516eea434e0d248
"""]]