RFC 1874 (rfc1874) - Page 3 of 6
SGML Media Types
Alternative Format: Original Text Document
RFC 1874 SGML Media Types December 1995
2.3. SGML Sub-type Parameters
The parameters for the Text/ and Application/SGML subtypes are
defined below.
charset The charset parameter for Text/SGML is defined in
[RFC-1521], the valid values and their meaning are
registered by the Internet Assigned Numbers
Authority (IANA) [RFC-1590]. The default charset
value for all Text content-types is "us-ascii"
[RFC-1521].
The charset parameter is provided to permit non-
SGML capable systems to provide reasonable
behavior when Text/SGML defaults to Text/Plain.
SGML capable systems will use the SGML-bctf param-
eter.
SGML-bctf The SGML-bctf (SGML bit combination transformation
format) parameter describes the method used to
transform the entity's sequence of constant width
binary numbers (called "bit combinations" in [ISO
8879, 4.24]) into the octet stream contained in
the MIME body part.
Valid values for SGML-bctf are the BCTF notation
names defined in Annex C of [ISO-10744] and are
reproduced for convenience in the Appendix. The
default value is "identity", i.e. perform no
transformation.
SGML-boot The SGML-boot parameter value is the content-ID of
a MIME body part (Application/Octet-stream) that
satisfies the requirements of the boot attribute
in [ISO-10744]. The Appendix contains a summary
of those requirements. The SGML-boot parameter is
only applicable if the SGML entity is a document
entity.
3. Security Considerations
SGML entities contain information to be parsed and processed by the
recipient's SGML system. Those entities may contain and such systems
may permit explicit system level commands to be execute while
processing the data. To the extent that an SGML system will execute
arbitrary command strings recipients of SGML entities may be at risk.
Levinson Experimental