PHP’s default upload limit is a maximum of 2M. If you want to upload files exceeding this setting, you need to adjust some parameters of PHP, apache, etc. Below, we briefly introduce some parameters involved in PHP file upload:
- file_uploads: whether to allow file uploading via HTTP switch, the default is ON.
- upload_tmp_dir: upload_tmp_dir is used to describe the temporary directory where files uploaded by PHP are placed. If you want to upload files, you must ensure that the server does not close the temporary files and has write permission to the folder. If not specified, PHP uses the system default value.
- upload_max_filesize: The maximum allowed upload file size, the default is 2M.
- post_max_size: Controls the maximum amount of data that PHP can receive during a form submission using the POST method. If you want to use the PHP file upload function, you need to change this value to be larger than upload_max_filesize.
- max_input_time: Limit the time of receiving data through POST, GET and PUT in seconds. If your application is running on a slow link, you may need to increase this value to accommodate the additional time required to receive data.
- memory_limit: In order to avoid running scripts from using a large amount of system available memory, PHP allows defining memory usage limits. Use the memory_limit variable to specify the maximum memory capacity that a single script can use. The value of the variable memory_limit should be appropriately larger than the value of post_max_size.
- max_execution_time: max_execution_time sets the time that PHP waits for the script to complete before forcibly terminating the script. This time is calculated in seconds. This variable is useful when the script enters an infinite loop. However, this feature can also cause the operation to fail when there is a legitimate activity that takes a long time to complete (such as uploading a large file). In such cases, you must consider increasing the value of this variable to prevent PHP from shutting down the script while it is performing some important process.
For Linux hosts, there may be a php.conf file under /etc/httpd/conf.d/access.conf/. This file may solve the file size limit problem of some systems.
The above introduces the PHP file upload restrictions, including relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.