WordPress tmp API example for https://core.trac.wordpress.org/ticket/31138

WP tmp API example

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TEMPORARY DIRECTORY: This is where plugin / theme authors can store temporary files and directories. When a temporary directory expires, the garbage collector will delete it.

* '''tmp_dir_create'''( $expiration, $primary_file )
 * ==> string $absolute_path | WP_Error $error
 * Create a temporary directory specifically for the plugin/theme defined by $primary_file.

* '''tmp_dir_info'''( $absolute_path, $with_listing = false ) 
 * ==> array $tmp_info | WP_Error $error
 * Get info about the temporary directory at $absolute_path.
 * $tmp_info contains $primary_file, $absolute_path, $expiration time and a (recursively obtained) file listing, if requested.

* '''tmp_dir_expire'''( $absolute_path )
 * ==> WP_Error $error
 * Allow the garbage collector to delete the temporary directory ASAP, together with its transient.

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TEMPORARY BACKUP: This is how plugin / theme authors can take advantage of the same temporary backup API internally used by WordPress 4.2. (This is a lie at the moment... my patch is not exactly like this :-)

* '''tmp_backup_create'''( $expiration, $primary_file, $relative_path = './' ) 
 * ==> string $backup_name | WP_Error $error
 * Recursively backup anything inside $relative_path, relative to the directory of the $primary_file.
 * The location of this backup could be different from that of a temporary directory.

* '''tmp_backup_info'''( $backup_name, $with_listing = false ) 
 * ==> array $backup_info | WP_Error $error
 * Get info about the backup whose name is $backup_name.
 * $backup_info contains primary file, relative_path, backup path, expiration time and a recursive file listing, if requested.

* '''tmp_backup_expire'''( $backup_name ) 
 * ==> WP_Error $error
 * Allow the garbage collector to delete the backup ASAP, together with its transient.

* '''tmp_backup_find_like'''( $backup_name ) 
 * ==> array $backups | WP_Error $error
 * Get the names of all the currently non-expired backups whose names share the same prefix of $backup_name.
 * Items sorted from older to newer.

* '''tmp_backup_expire_like'''( $backup_name ) 
 * ==> WP_Error $error
 * Allow the garbage collector to delete all the currently non-expired backups whose names share the same prefix of $backup_name ASAP, together with their transients.

* '''tmp_backup_find_all'''( $primary_file ) 
 * ==> array $all_names | WP_Error $error
 * Get the names of all the currently non-expired backups for $primary_file.
 * Items sorted from older to newer.

* '''tmp_backup_expire_all'''( $primary_file ) 
 * ==> WP_Error $error
 * Allow the garbage collector to delete all the backups ASAP, together with their transients.