Function

Summary

Tries to work out the external format

Package

system

Signature

guess-external-format pathname ef-spec buffer length => ef-spec

Arguments

pathname

Pathname identifying location of buffer.

ef-spec

An external format spec.

buffer

A buffer whose contents are examined.

length

Length (an integer) up to which buffer should be examined.

Values

ef-spec

An external format spec.

Description

If ef-spec is complete, then it is returned. Otherwise guess-external-format calls, in turn, functions on the list *file-encoding-detection-algorithm*. If a complete external format spec is returned it is used, otherwise the return value is passed to the next function. If the name of the external format spec returned by the last function on this list is :default, an error of type file-encoding-resolution-error is signaled. The caller offers a restart for trying again with respecified external-format and/or element-type arguments. Otherwise guess-external-format proceeds to guess the eol-style.

To guess the eol-style, functions on the list *file-eol-style-detection-algorithm* are called in turn. If a complete external format spec is returned it is used, otherwise the return value is passed to the next function. If the external format spec returned by the last function on this list does not contain :eol-style, an error of type file-encoding-resolution-error is signaled.

See also

*file-encoding-detection-algorithm*
*file-eol-style-detection-algorithm*
file-encoding-resolution-error