http_dispatch:http_reply

Options is a list of

cache(+Boolean): If true (default), handle If-modified-since and send modification time.
mime_type(+Type): Overrule mime-type guessing from the filename as provided by file_mime_type/2.
static_gzip(+Boolean): If true (default false) and, in addition to the plain file, there is a .gz file that is not older than the plain file and the client acceps gzip encoding, send the compressed file with Transfer-encoding: gzip.
cached_gzip(+Boolean): If true (default false) the system maintains cached gzipped files in a directory accessible using the file search path http_gzip_cache and serves these similar to the static_gzip(true) option. If the gzip file does not exist or is older than the input the file is recreated.
unsafe(+Boolean): If false (default), validate that FileSpec does not contain references to parent directories. E.g., specifications such as www('../../etc/passwd') are not allowed.
headers(+List): Provides additional reply-header fields, encoded as a list of Field(Value).

If caching is not disabled, it processes the request headers If-modified-since and Range.