sgmls.man

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.TH SGMLS 1
.SH NAME
sgmls \- a validating SGML parser
.sp
An \*S System Conforming to
.if n .br
International Standard ISO 8879 \(em
.br
Standard Generalized Markup Language
.SH SYNOPSIS
.B sgmls
[
.B \-deglprsuv
]
[
.BI \-c file
]
.if \n(Os=1 \{\
[
.BI \-f file
]
.\}
[
.BI \-i name
]
[
.BI \-m file
]
.if \n(Tr \{\
[
.BI \-x flags
]
[
.BI \-y flags
]
.\}
[
.I filename\|.\|.\|.
]
.SH DESCRIPTION
.I Sgmls
parses and validates
the \*S document entity in
.I filename\|.\|.\|.
and prints on the standard output a simple \s-1ASCII\s0 representation of its
Element Structure Information Set.
(This is the information set which a structure-controlled
conforming \*S application should act upon.)
Note that the document entity may be spread amongst several files;
for example, the SGML declaration, document type declaration and document
instance set could each be in a separate file.
If no filenames are specified, then
.I sgmls
will read the document entity from the standard input.
A filename of
.B \-
can also be used to refer to the standard input.
.LP
The following options are available:
.TP
.BI \-c file
Report any capacity limits that are exceeded
and write a report of capacity usage to
.IR file .
The report is in the format of a RACT result.
RACT is the Reference Application for Capacity Testing defined in the
Proposed American National Standard
.I
Conformance Testing for Standard Generalized Markup Language (SGL) Systems
(X3.190-199X),
Draft July 1991.
.TP
.B \-d
Warn about duplicate entity declarations.
.TP
.B \-e
Describe open entities in error messages.
Error messages always include the position of the most recently
opened external entity.
.if \n(Os=1 \{\
.TP
.BI \-f file
Redirect errors to
.IR file .
.\}
.TP
.B \-g
Show the \s-1GI\s0s of open elements in error messages.
.TP
.BI \-i name
Pretend that
.RS
.IP
.BI <!ENTITY\ %\  name\  \(tsINCLUDE\(ts>
.LP
occurs at the start of the document type declaration subset
in the \*S document entity.
Since repeated definitions of an entity are ignored,
this definition will take precedence over any other definitions
of this entity in the document type declaration.
Multiple
.B \-i
options are allowed.
If the \*S declaration replaces the reserved name
.B INCLUDE
then the new reserved name will be the replacement text of the entity.
Typically the document type declaration will contain
.IP
.BI <!ENTITY\ %\  name\  \(tsIGNORE\(ts>
.LP
and will use
.BI % name ;
in the status keyword specification of a marked section declaration.
In this case the effect of the option will be to cause the marked
section not to be ignored.
.RE
.TP
.B \-l
Output
.B L
commands giving the current line number and filename.
.TP
.BI \-m file
Map public identifiers and entity names to system identifiers
using the catalog entry file
.IR file .
Multiple
.B \-m
options are allowed.
Catalog entry files specified with the
.B -m
option will be searched before the defaults.
.TP
.B \-p
Parse only the prolog.
.I Sgmls
will exit after parsing the document type declaration.
Implies
.BR \-s .
.TP
.B \-r
Warn about defaulted references.
.TP
.B \-s
Suppress output.
Error messages will still be printed.
.TP
.B \-u
Warn about undefined elements: elements used in the DTD but not defined.
.TP
.B \-v
Print the version number.
.if \n(Tr \{\
.TP
.BI \-x flags
.br
.ns
.TP
.BI \-y flags
Enable debugging output;
.B \-x
applies to the document body,
.B \-y
to the prolog.
Each character in the
.I flags
argument enables tracing of a particular activity.
.RS
.TP
.B t
Trace state transitions.
.TP
.B a
Trace attribute activity.
.TP
.B c
Trace context checking.
.TP
.B d
Trace declaration parsing.
.TP
.B e
Trace entities.
.TP
.B g
Trace groups.
.TP
.B i
Trace \s-1ID\s0s.
.TP
.B m
Trace marked sections.
.TP
.B n
Trace notations.
.RE
.\}
.SS "Entity Manager"
An external entity resides in one or more files.
The entity manager component of
.I sgmls
maps a sequence of files into an entity in three sequential stages:
.IP 1.
each carriage return character is turned into a non-SGML character;
.IP 2.
each newline character is turned into a record end character,
and at the same time
a record start character is inserted at the beginning of each line;
.IP 3.
the files are concatenated.
.LP
A system identifier is
interpreted as a list of filenames separated by
.if \n(Os=0 colons.
.if \n(Os=1 semi-colons.
A filename of
.B \-
can be used to refer to the standard input.
.LP
If a system identifier is not specified,
then the entity manager can generate one using catalog
entry files in the format defined in the SGML Open Draft Technical
Resolution on Entity Management.  A catalog entry file contains a
sequence of entries in one of the following four forms:
.TP
.BI PUBLIC\  pubid\ sysid
This specifies that
.I sysid
should be used as the system identifier if the the public
identifier is
.IR pubid .
.I Sysid
is a system identifier as defined in ISO 8879 and
.I pubid
is a public identifier as defined in ISO 8879.
.TP
.BI ENTITY\  name\ sysid
This specifies that
.I sysid
should be used as the system identifier if the entity is a general
entity whose name is
.IR name .
.TP
.BI ENTITY\ % name\ sysid
This specifies that
.I sysid
should be used as the system identifier if the entity is a parameter
entity whose name is
.IR name .
Note that there is no space between the
.B %
and the
.IR name .
.TP
.BI DOCTYPE\  name\ sysid
This specifies that
.I sysid
should be used as the system identifier if the entity is an
entity declared in a document type declaration whose document type name is
.IR name .
.LP
The last two forms are extensions to the SGML Open format.
The delimiters can be omitted from the
.I sysid
provided it does not contain any white space.
Comments are allowed between parameters delimited by
.B --
as in SGML.
The environment variable
.B \s-1SGML_CATALOG_FILES\s0
contains a
.if \n(Os=0 colon-separated
.if \n(Os=1 semicolon-separated
list of catalog entry files.
These will be searched after any catalog entry files specified
using the
.B \-m
option.
If this environment variable is not set,
then a system dependent list of catalog entry files will be used.
A match in a catalog entry file for a PUBLIC entry will take
precedence over a match in the same file for an ENTITY
or DOCTYPE entry.
A filename in a system identifier in a catalog entry file
is interpreted relative to the directory containing the catalog
entry file.
.LP
If no match can be found in a catalog entry file, then the entity
manager will attempt to generate a filename using the public
identifier (if there is one) and other information available to it.
Notation identifiers are not subject to this treatment.  This process
is controlled by the environment variable
.BR \s-1SGML_PATH\s0 ;
this contains a
.if \n(Os=0 colon-separated
.if \n(Os=1 semicolon-separated
list of filename templates.
A filename template is a filename that may contain
substitution fields; a substitution field is a
.B %
character followed by a single letter that indicates the value
of the substitution.
The value of a substitution can either be a string
or it can be
.IR null .
The entity manager transforms the list of
filename templates into a list of filenames by substituting for each
substitution field and discarding any template
that contained a substitution field whose value was null.
It then uses the first resulting filename that exists and is readable.
Substitution values are transformed before being used for substitution:
firstly, any names that were subject to upper case substitution
are folded to lower case;
secondly,
.if \n(Os=0 \{\
.\" Unix
space characters are mapped to underscores
and slashes are mapped to percents.
.\}
.if \n(Os=1 \{\
.\" MS-DOS
the characters
.B +,./:=?
and space characters are deleted.
.\}
The value of the
.B %S
field is not transformed.
The values of substitution fields are as follows:
.TP
.B %%
A single
.BR % .
.TP
.B %D
The entity's data content notation.
This substitution will succeed only for external data entities.
.TP
.B %N
The entity, notation or document type name.
.TP
.B %P
The public identifier if there was a public identifier,
otherwise null.
.TP
.B %S
The system identifier if there was a system identifier
otherwise null.
.TP
.B %X
(This is provided mainly for compatibility with \s-1ARCSGML\s0.)
A three-letter string chosen as follows:
.LP
.RS
.ne 11
.TS
tab(&);
c|c|c s
c|c|c s
c|c|c|c
c|c|c|c
l|lB|lB|lB.
&&With public identifier
&&_
&No public&Device&Device
&identifier&independent&dependent
_
Data or subdocument entity&nsd&pns&vns
General SGML text entity&gml&pge&vge
Parameter entity&spe&ppe&vpe
Document type definition&dtd&pdt&vdt
Link process definition&lpd&plp&vlp
.TE
.LP
The device dependent version is selected if the public text class
allows a public text display version but no public text display
version was specified.
.RE
.TP
.B %Y
The type of thing for which the filename is being generated:
.TS
tab(&);
l lB.
SGML subdocument entity&sgml
Data entity&data
General text entity&text
Parameter entity&parm
Document type definition&dtd
Link process definition&lpd
.TE
.LP
The value of the following substitution fields will be null
unless a valid formal public identifier was supplied.
.TP
.B %A
Null if the text identifier in the
formal public identifier contains an unavailable text indicator,
otherwise the empty string.
.TP
.B %C
The public text class, mapped to lower case.
.TP
.B %E
The public text designating sequence (escape sequence)
if the public text class is
.BR \s-1CHARSET\s0 ,
otherwise null.
.TP
.B %I
The empty string if the owner identifier in the formal public identifier
is an \s-1ISO\s0 owner identifier,
otherwise null.
.TP
.B %L
The public text language, mapped to lower case,
unless the public text class is
.BR \s-1CHARSET\s0 ,
in which case null.
.TP
.B %O
The owner identifier (with the
.B +//
or
.B \-//
prefix stripped.)
.TP
.B %R
The empty string if the owner identifier in the formal public identifier
is a registered owner identifier,
otherwise null.
.TP
.B %T
The public text description.
.TP
.B %U
The empty string if the owner identifier in the formal public identifier
is an unregistered owner identifier,
otherwise null.
.TP
.B %V
The public text display version.
This substitution will be null if the public text class
does not allow a display version or if no version was specified.
If an empty version was specified, a value of
.B default
will be used.
.LP
Normally if the external identifier for an entity includes a system
identifier, the entity manager will use the specified system
identifier and not attempt to generate one.
If, however,
.B \s-1SGML_PATH\s0
uses the
.B %S
field,
then the entity manager will first search for a matching
entry in the catalog entry files.
If a match is found, then this will be used instead of the
specified system identifier.
Otherwise,
if the specified system identifier does not contain any
.if \n(Os=0 colons,
.if \n(Os=1 semi-colons,