null value to Filesystem::isAbsolutePath() is deprecated and will be removed in 5.0Filesystem::dumpFile() is deprecated and will be removed in 5.0Filesystem::appendToFile() is deprecated and will be removed in 5.0LockHandlerFilesystem::makePathRelative() has been removed.Filesystem::makePathRelative() is deprecated and will be removed in 4.0appendToFile() to append contents to existing filesreadlink() as a platform independent method to read links$mode argument from Filesystem::dumpFile()24eb396 : BC Break : mkdir() function now throws exception in case of failure instead of returning Boolean value