How to put the name of the file in advance when uploading? : I want to save the uploaded file with "1.jpg" name. If it already exists in the "upload" folder, save with "2.jpg", and if file "2.jpg" already exists in the "upload" folder, Wait until the another script clears one of them. If, after some time (about 120 seconds), none of the two files was erased, it will display an error message. What code should I use?