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Opening, Referencing, and Saving Files
When specifying a file path and name or a directory path, you can provide a file system path or a URL as a file reference. This means that for documents, graphics, entities, arguments of ACL commands and functions, system IDs, in an href for stylesheet associations, or other file specifications, you can supply a file or path reference using:
the path conventions supported by your operating system
a URL following the http://, https:// or file:// protocols
Editing a file referenced by a URL means that write access to it requires special handling for opening, locking, and saving files. Generally, if a file is opened through WebDAV (on Windows only) or a repository adapter HTTP URL, then it can be edited; otherwise, the file referenced by URL is available read-only. Using read-only URL references are suitable for inserting graphic references from a web server, opening file entities for viewing within a parent document, and specifying stylesheet locations.
For Arbortext Editor users sending publishing requests to the Arbortext PE Request Manager, the URL to specify Arbortext Publishing Engine can be either HTTP or HTTPS. Refer to Using Arbortext Publishing Engine for publishing documents and the set peserverurl command for more information.
You can't use a URL to specify the location of a custom directory (using the APTCUSTOM environment variable) or an application directory (using the APTAPPLICATION environment variable).