Portable application description

from Wikipedia, the free encyclopedia

Portable Application Description ( PAD for short ) is an XML format for the standardized description of software by the manufacturer, which was invented by the Association of Shareware Professionals . The software manufacturer stores information about a specific program, such as the version, download URL, license or program icon, in a PAD file. Corresponding programs or web services can now process this information, since it is available in a standardized format, and prepare it for the user. Since the PAD file also contains the URI of the pad file itself, an automatic update service is possible, which indicates new versions of all programs for which a PAD file exists in good time (not every program needs its own update check). This function is already supported by many large download archives and thus largely automates the distribution of program updates.

PAD especially meets the demands of shareware in terms of information.

construction

The root element of a PAD is XML_DIZ_INFO , which contains the following child nodes:

MASTER_PAD_VERSION_INFO
Information about the PAD
Company_Info
Contact information about the manufacturer such as company name, address and contact person
Program_Info
Information about the software such as version, type of application (e.g. editor), operating system, but also purchase price
Program_Descriptions
Descriptions of the program (maximum length specified in fields, Char_Desc_250 may contain a maximum of 250 characters). This element supports localization through various child nodes such as English or German .
Web_Info
Online resources such as homepage, download URI, screenshot, program icon and path to the PAD
Permissions
License information

Expandability

The PAD specification also provides that you can define your own elements. However, this is not implemented, as is typical for XML, using XML namespaces, but rather using tags whose names begin with a specific character string; it is therefore a separate namespace concept. For example, if a software manufacturer defines the "namespace" MyCompany, all elements of the namespace begin with MyCompany_ . However, this makes the validation of PAD files more difficult with the help of a document type definition (DTD) or an XML schema .

pad.txt

Together with PAD files, the manufacturer of the editor DeuPAD suggests the pad.txt standard: Analogous to the robots.txt , a pad.txt (in ASCII format) should be located in the root directory of a website , in which the (complete ) URI for a PAD file: 

http://www.example.com/stable_product/pad_file.xml
http://www.example.com/YetAnotherProduct/pad_file.xml
…

Web links