$ _ FILES ['userfile'] ['error'] error code (from the PHP manual)

Chapter 38. File Upload Processing
 

Error Message description
Starting from PHP 4.2.0, PHP will return a corresponding error along with the array of File InformationCode. This code can be found in the error field of the file array generated during file upload, that is, $ _ FILES ['userfile'] ['error'].

Upload_err_ OK
The value is 0. If no error occurs, the file is uploaded successfully.

Upload_err_ini_size
The value is 1, and the uploaded file exceeds the limit of the upload_max_filesize option in PHP. ini.

Upload_err_form_size
The value is 2, and the size of the uploaded file exceeds the value specified by the max_file_size option in the HTML form.

Upload_err_partial
The value is 3, and only part of the file is uploaded.

Upload_err_no_file
The value is 4 and no file is uploaded.

Upload_err_no_tmp_dir
The value is 6 and the Temporary Folder cannot be found. PHP 4.3.10 and PHP 5.0.3 are introduced.

Upload_err_cant_write
If the value is 7, the file fails to be written. PHP 5.1.0 is introduced.

Note: The above value is changed to a PHP constant after PHP 4.3.0.

 

 

The above is taken from the PHP Chinese manual, meaning of error ~