Please not that using svn_log without giving revisions is much, much slower then with revisions. Examples:
$ time php -r "svn_log('http://localhost/svn/shopadsl');"
$ time php -r "svn_log('http://localhost/svn/shopadsl', 0, 45);"
(PECL svn >= 0.1.0)
svn_log — Returns the commit log messages of a repository URL
$limit= 0 [, int
$flags= SVN_DISCOVER_CHANGED_PATHS | SVN_STOP_ON_COPY ]]]] )
svn_log() returns the complete history of the item at the repository URL
repos_url, or the history of a specific revision
start_revision is set. This function is equivalent
svn log --verbose -r $start_revision $repos_url.
Repository URL of the item to retrieve log history from.
Revision number of the first log to retrieve. Use
SVN_REVISION_HEADto retrieve the log from the most recent revision.
Revision number of the last log to retrieve. Defaults to
start_revisionif specified or to
Number of logs to retrieve.
Any combination of
On success, this function returns an array file listing in the format of:
 => Array, ordered most recent (highest) revision first ( [rev] => integer revision number [author] => string author name [msg] => string log message [date] => string date formatted per ISO 8601, i.e. date('c') [paths] => Array, describing changed files (  => Array ( [action] => string letter signifying change [path] => absolute repository path of changed file )  => ... ) )  => ...
The output will always be a numerically indexed array of arrays, even when there are none or only one log message(s).
The value of action is a subset of the » status output in the first column, where possible values are:
|M||Item/props was modified|
|A||Item was added|
|D||Item was deleted|
|R||Item was replaced|
If no changes were made to the item, an empty array is returned.
This function is EXPERIMENTAL. The behaviour of this function, its name, and surrounding documentation may change without notice in a future release of PHP. This function should be used at your own risk.
Example #1 svn_log() example
print_r( svn_log('http://www.example.com/', 23) );
The above example will output something similar to:
Array (  => Array ( [rev] => 23 [author] => 'joe' [msg] => 'Add cheese and salami to our sandwich.' [date] => '2007-04-06T16:00:27-04:00' [paths] => Array (  => Array ( [action] => 'M' [path] => '/sandwich.txt' ) ) ) )