Alternatives
In network contexts, files are regarded as streams of bits and do not have filenames or extensions.
In many internet protocols such as HTTP and MIME email, the type of a bitstream is stated as the internet media type of the stream (also called the MIME type or content type). This is given in a line of text preceding the stream, such as:
Content-type: text/plain
Because there is no standard mapping between filename extensions and internet media types, mismatches in file type interpretation between authors, web servers, and client software can be a source of errors when transferring files over the internet. For instance, a content author may specify a .svgz extension on a compressed Scalable Vector Graphics file, but a web server which does not recognize this extension may not send the proper content type of application/svg+xml and its required compression header, leaving web browsers unable to correctly interpret and display the image.
BeOS, whose BFS file system supports extended attributes, would tag a file with its internet media type as an extended attribute. The KDE and GNOME desktop environments associate an internet media type with a file by examining both the filename suffix and the contents of the file, in the fashion of the file command, as a heuristic. They choose the application to launch when a file is opened based on that internet media type, reducing the dependency on filename extensions. Mac OS X uses both filename extensions and media types, as well as file type codes, to select a Uniform Type Identifier by which to identify the file type internally.
Read more about this topic: Filename Extension
Famous quotes containing the word alternatives:
“The last alternatives they face
Of face, without the life to save,
Being from all salvation weaned
A stag charged both at heel and head:
Who would come back is turned a fiend
Instructed by the fiery dead.”
—Allen Tate (1899–1979)
“Clearly, society has a tremendous stake in insisting on a woman’s natural fitness for the career of mother: the alternatives are all too expensive.”
—Ann Oakley (b. 1944)
“The literal alternatives to [abortion] are suicide, motherhood, and, some would add, madness. Consequently, there is some confusion, discomfort, and cynicism greeting efforts to “find” or “emphasize” or “identify” alternatives to abortion.”
—Connie J. Downey (b. 1934)