Since a temporary file is not a real file, some inherited methods will not work. For example,
* SplFileInfo::isReadable() and SplFileInfo::isWritable() return false, not because it was unreadable or unwritable, but because the file does not exists.
* SplFileObject::flock() fails and returns false.
* SplFileInfo::getATime(), SplFileInfo::getCTime(), SplFileInfo::getMTime(), SplFileInfo::getOwner(), SplFileInfo::getGroup(), SplFileInfo::getInode(), SplFileInfo::getPerms(), and SplFileInfo::getSize() throw RuntimeException "stat failed for php://temp". However, SplFileObject::fstat() succeeds and returns atime = mtime = ctime = uid = gid = ino = 0 together with the correct size.
* SplFileInfo::getType throws RuntimeException "Lstat failed for php://temp".
* SplFileInfo::getLinkTarget throws RuntimeException "Unable to read link php://temp, error: No such file or directory".