Short Contents
**************
Gamma
1 Overview
2 Syslog Interface
3 SQL Interface
4 Expat Interface
5 How to Report a Bug
Appendix A GNU Free Documentation License
Concept Index
Table of Contents
*****************
Gamma
1 Overview
2 Syslog Interface
3 SQL Interface
4 Expat Interface
4.1 Expat Basics
4.2 Creating XML Parsers
4.3 Parser Functions
4.4 Error Handling
4.5 Expat Handlers
4.5.1 start-element-handler
4.5.2 end-element-handler
4.5.3 character-data-handler
4.5.4 processing-instruction-handler
4.5.5 comment-handler
4.5.6 start-cdata-section-handler
4.5.7 end-cdata-section-handler
4.5.8 default-handler
4.5.9 default-handler-expand
4.5.10 skipped-entity-handler
4.5.11 start-namespace-decl-handler
4.5.12 end-namespace-decl-handler
4.5.13 xml-decl-handler
4.5.14 start-doctype-decl-handler
4.5.15 end-doctype-decl-handler
4.5.16 attlist-decl-handler
4.5.17 entity-decl-handler
4.5.18 notation-decl-handler
4.5.19 not-standalone-handler
4.6 miscellaneous functions
5 How to Report a Bug
Appendix A GNU Free Documentation License
A.1 ADDENDUM: How to use this License for your documents
Concept Index
Gamma
*****
This edition of the `Gamma Manual', last updated 20 March 2010,
documents `Gamma' Version 2.0.
1 Overview
**********
`Gamma' is a collection of assorted Guile modules. Version 2.0
provides a `syslog' interface, a module for interfacing with SQL (more
precisely: MySQL and PostgreSQL) databases and a module for writing XML
parsers,
2 Syslog Interface
******************
The `(gamma syslog)' module provides bindings for `syslog' functions:
(use-modules ((gamma syslog)))
-- Scheme procedure: openlog tag option facility
Opens a connection to the system logger for Guile program.
Arguments have the same meaning as in openlog(3):
TAG
Syslog "tag": a string that will be prepended to every
message.
OPTION
Flags that control the operation. A logical or (`logior') of
one or more of the following:
LOG_CONS
Write directly to system console if there is an error
while sending to system logger.
LOG_NDELAY
Open the connection immediately (normally, the opening
is delayed until when the first message is logged).
LOG_NOWAIT
Don't wait for child processes that may have been
created while logging the message.
LOG_ODELAY
The converse of `LOG_NDELAY'; opening of the connection
is delayed until `syslog' is called. This is the
default.
LOG_PERROR
Print to stderr as well. This constant may be absent if
the underlying implementation does not support it.
LOG_PID
Include PID with each message.
FACILITY
Specifies what type of program is logging the message. The
facility must be one of:
Facility Meaning
----------------------------------------------------------------
LOG_AUTH Security/authorization messages.
LOG_AUTHPRIV Same as `LOG_AUTH'.
LOG_CRON Clock daemon.
LOG_DAEMON System daemons without separate facility
value.
LOG_FTP FTP daemon.
LOG_LOCAL0 through Reserved for local use.
LOG_LOCAL7
LOG_LPR Line printer subsystem.
LOG_MAIL Mail subsystem.
LOG_NEWS USENET news subsystem.
LOG_SYSLOG Messages generated internally by `syslogd'.
LOG_USER Generic user-level messages. This is the
default.
LOG_UUCP UUCP subsystem.
Example:
(openlog "reader" (logior LOG_PID LOG_CONS) LOG_DAEMON)
-- Scheme procedure: syslog-tag
Returns the tag, used in the recent call to `openlog'.
-- Scheme procedure: syslog prio text
Distribute a message via `syslogd'. The TEXT supplies the message
text. The PRIO specifies "priority" of the message. Its value
must be one of the following:
Priority Meaning
---------------------------------------------------------------------
LOG_EMERG system is unusable
LOG_ALERT action must be taken immediately
LOG_CRIT critical conditions
LOG_ERR error conditions
LOG_WARNING warning conditions
LOG_NOTICE normal, but significant, condition
LOG_INFO informational message
LOG_DEBUG debug-level message
Example:
(syslog LOG_WARNING "This is a test message")
The priority argument may also be `OR'ed with a facility value, to
override the one set by the `openlog' function, e.g.:
(syslog (logior LOG_DAEMON LOG_WARNING) "This is a test message")
It is common to use the `format' function to prepare the value of
the TEXT argument:
(syslog LOG_WARNING
(format #f "operation reported: ~A" result))
-- Scheme procedure: open-syslog-port prio
Create a "syslog port" for the given priority. Syslog port is a
special output port such that any writes to it are transferred to
the syslog with the given priority. The port is line buffered.
For example, the following code:
(set-current-output-port (open-syslog-port LOG_ERR))
(display "A test ")
(display "message")
(newline)
results in sending the string `A test message' to the syslog
priority `LOG_ERR'.
-- Scheme procedure: openlog?
Return `#t' if `openlog' was previously called.
-- Scheme procedure: closelog
Close the logging channel. The use of this function is optional.
3 SQL Interface
***************
The `(gamma sql)' module provides interface with MySQL and PostgreSQL
database management systems.
Usage:
(use-modules ((gamma sql)))
-- Scheme procedure: sql-open-connection params
This function opens a connection to the SQL server and returns a
connection object. This object is then used as argument to
`sql-query' and `sql-close-connection' functions.
The `params' argument supplies the connection parameters. It is a
list of conses, each of which is composed from a keyword and a
value.
-- Keyword: #:iface
Defines the type of the SQL interface. Valid values are:
`"mysql"', to connect to a MySQL server, and `"pgsql"', to
connect to a Postgres server.
-- Keyword: #:host
Defines server host name. The value is a string, containing
the host name or ASCII representation of the host IP address.
-- Keyword: #:port
Defines the port number server is listening on. The value is
a decimal port number.
-- Keyword: #:socket
If the SQL server is listening on a socket, this keyword
defines the UNIX pathname of the socket. This keyword cannot
be used together with `#:host' or `#:port' keyword pairs.
-- Keyword: #:user
Sets the SQL user name.
-- Keyword: #:pass
Sets the SQL user password.
-- Keyword: #:db
Sets the database name.
-- Keyword: #:ssl-cert
Defines full pathname of the SSL certificate to use. If this
keyword is present, the connection with the server will be
encrypted using SSL.
Currently it is implemented only for MySQL connections.
-- Keyword: #:config-file
Use the specified MySQL configuration file to obtain missing
parameters.
-- Keyword: #:config-group
Obtain missing parameters from the specified group in the
MySQL configuration file (see `#:config-file', above).
-- Scheme procedure: sql-close-connection conn
Close the SQL connection. The CONN must be a connection
descriptor returned from a previous call to `sql-open-connection'.
-- Scheme procedure: sql-query conn query
CONN is a connection descriptor returned from a previous call to
`sql-open-connection', and QUERY is a valid SQL query. This
function executes the query and returns its results.
If QUERY is a `SELECT' query (or a similar query, returning
tuples), the return is a list, each element of which is a list
representing a row. Elements of each row ("columns") are string
values.
If QUERY results in some modifications to the database (e.g. an
`UPDATE' statement), the `sql-query' function returns the number
of affected database rows.
-- Error Keyword: sql-error
An error of this type is raised when any of the above functions
fails. Two arguments are supplied: a string describing the error,
and error message from the underlying SQL implementation.
-- Scheme syntax: sql-catch-failure (handler) expr
-- Scheme syntax: sql-catch-failure expr
This syntax executes the Scheme expression EXPR and calls
`handler' if a `gsql-error' exception occurs. In its second form,
`sql-catch-failure' calls a function named `sql-error-handler' if
a `sql-error' exception occurs. The `sql-error-handler' must be
declared by the user.
The error handler must be declared as follows:
(define (handler key func fmt fmtargs data)
...)
where:
KEY
The error key (`sql-error').
FUNC
Name of the Scheme function that encountered the error.
FMT
Format string suitable for `format'.
FMTARGS
Arguments to FMT.
DATA
Interface-specific error description. It is a list
consisting of two elements. The first element is an integer
code of the error, if supported by the underlying
implementation, or `#f' if not. The second element is a
textual description of the error obtained from the underlying
implementation.
For example:
(define (sql-error-handler key func fmt fmtargs data)
(apply format (current-error-port) fmt fmtargs))
-- Scheme syntax: sql-ignore-failure (value) expr
-- Scheme syntax: sql-ignore-failure expr
Evaluates Scheme expression EXPR and returns the result of
evaluation, or VALUE if a `gsql-error' exception occurs.
In its second form, returns `#f' in case of error.
4 Expat Interface
*****************
The `(gamma expat)' module provides interface to `libexpat', a library
for parsing XML documents. See `http://expat.sourceforge.net', for a
description of the library.
Usage:
(use-modules ((gamma expat)))
4.1 Expat Basics
================
Parsing of XML documents using Expat is based on user-defined callback
functions. You create a "parser" object, and associate "callback" (or
"handler") functions with the events he is interested in. Such events
may be, for instance, encountering of a open or closing tag,
encountering of a comment block, etc. Once the parser object is ready,
you start feeding the document to it. As the parser recognizes XML
constructs, it calls the callbacks that are registered for them.
Parsers are created using `xml-make-parser' function. In the
simplest case, it takes no arguments, e.g.:
(let ((parser (xml-make-parser)))
...
The function `xml-parse' takes the parser as its argument, reads the
document from the current input stream and feeds it to the parser.
Thus, the simplest program for parsing XML documents is:
(use-modules ((gamma expat)))
(xml-parse (xml-make-parser))
This program is perhaps not so useful, but you may already use it to
check whether its input is a correctly formed XML document. If
`xml-parse' encounters an error, it signals the `gamma-xml-error'
error. *Note error handling: errors, for a discussion on how to handle
it.
The `xml-make-parser' function takes optional arguments, which allow
to set callback functions for the new parser. For example, the
following code sets function `elt-start' as a handler for start
elements:
(xml-make-parser #:start-element-handler elt-start)
The `#:start-element-handler' keyword informs the function that the
argument following it is a handler for start XML documents. Any number
of handlers may be set this way, e.g.:
(xml-make-parser #:start-element-handler elt-start
#:end-element-handler elt-end
#:comment-handler comment)
Definitions of particular handler functions differ depending on their
purpose, i.e. on the event they are defined to handle. For example, a
start element handler must be defined as having two arguments. First
of them is the name of the tag, and the second one is a list of
attributes supplied for that tag. Thus, for example, the following
start handler prints the tag and the number of attributes:
(define (elt-start name attrs)
(format #t "~A (~A)~%" name (length attrs)))
For a detailed description of all available handlers and handler
keywords, see *note handlers::.
To further improve our example, suppose you need a program that will
take an XML document as its input and create a description of its
structure on output, showing element nesting levels by indenting their
description. Here is how to write it.
First, define handlers for start and end elements. Start element
handler will print two indenting spaces for each level of ancestor
elements, followed by the element name and its attributes and a
newline. It will then increase the global level variable:
(define level 0)
(define (elt-start name attrs)
(display (make-string (* 2 level) #\space))
(display name)
(for-each
(lambda (x)
(display " ")
(display (car x))
(display "=")
(display (cdr x)))
attrs)
(newline)
(set! level (1+ level)))
The handler for end tags is simpler: it must only decrease the level:
(define (elt-end name)
(set! level (1- level)))
Finally, create a parser and parse the input:
(xml-parse (xml-make-parser #:start-element-handler elt-start
#:end-element-handler elt-end))
4.2 Creating XML Parsers
========================
Gamma provides several functions for creating and modifying XML
parsers. The `xml-primitive-make-parser' and
`xml-primitive-set-handler' are lower level interfaces, provided for
those who wish to further extend Gamma functionality. Higher level
interfaces are `xml-make-parser' and `xml-set-handler' which we
recommend for regular users.
-- Scheme procedure: xml-primitive-make-parser enc sep
Return a new XML parser. If ENC is given, it must be one of:
`US-ASCII', `UTF-8', `UTF-16', `ISO-8859-1'. If SEP is given, the
returned parser has namespace processing in effect. In that case,
SEP is a character which is used as a separator between the
namespace URI and the local part of the name in returned namespace
element and attribute names.
-- Scheme procedure: xml-set-encoding parser enc
Set the encoding to be used by the PARSER. The latter must be a
value returned from a previous call to `xml-primitive-make-parser'
or `xml-make-parser'.
The sequence:
(let ((parser (xml-primitive-make-parser)))
(xml-set-encoding parser encoding)
...
is equivalent to:
(let ((parser (xml-primitive-make-parser encoding)))
...
and to:
(let ((parser (xml-make-parser encoding)))
...
-- Scheme procedure: xml-primitive-set-handler parser key handler
Set XML handler for an event. Arguments are:
PARSER
A valid XML parser
KEY
A key, identifying the event. For example,
`#:start-element-handler' sets handler which is called for
start tags.
*Note handlers::, for its values and their meaning.
HANDLER
Handler procedure.
-- Scheme function: xml-set-handler parser args...
Sets several handlers at once. Optional arguments (ARGS) are
constructed of keywords (as described in *note handler-keyword::),
followed by their arguments, for example:
(xml-set-handler parser
#:start-element-handler elt-start
#:end-element-handler elt-end)
-- Scheme function: xml-make-parser [enc [sep]] args...
Create a parser and set its handlers. Optional ENC and SEP have
the same meaning as in *note xml-primitive-make-parser::. The
rest of arguments define handlers for the new parser. They must
be supplied in pairs: a keyword (as described in *note
handler-keyword::), followed by its argument. For example:
(xml-make-parser "US-ASCII"
#:start-element-handler elt-start
#:end-element-handler elt-end)
This call creates a new parser for documents in `US-ASCII'
encoding and sets two handlers: for element start and for element
end. This call is equivalent to:
(let ((p (xml-primitive-make-parser "US-ASCII")))
(xml-primitive-set-handler p #:start-element-handler elt-start)
(xml-primitive-set-handler p #:end-element-handler elt-end)
...
4.3 Parser Functions
====================
-- Scheme procedure: xml-primitive-parse parser input isfinal
Parse next piece of input. Arguments are:
PARSER
A parser returned from a previous call to
`xml-primitive-make-parser' or `xml-make-parser'.
INPUT
A piece of input text.
ISFINAL
Boolean value indicating whether INPUT is the last part of
input.
-- Scheme function: xml-parse-more parser input
Equivalent to:
(xml-primitive-parse parser input #f)
unless INPUT is an end-of-file object, in which case it is
equivalent to:
(xml-primitive-parse parser "" #t)
-- Scheme function: xml-parse parser [port]
Reads XML input from PORT (or the standard input port, if it is
not given) and parses it using `xml-primitive-parse'.
4.4 Error Handling
==================
When encountering an error. the `gamma xml' functions use Guile error
reporting mechanism (*note Procedures for Signaling Errors:
(guile)Error Reporting.). The "error key" indicates what type of error
it was, and the rest of arguments supply additional information about
the error. Recommended ways for handling errors in Guile are described
in *note How to Handle Errors: (guile)Handling Errors.). In this
chapter we will describe how to handle errors in XML input and other
errors reported by the underlying `libexpat' library.
-- Error Key: gamma-xml-error
An error of this type is signalled when a of `gamma xml' functions
encounters an XML-related error.
The arguments supplied with this error are:
key
The error key (`gamma-xml-error').
func
Name of the function that generated the error.
fmt
Format string
fmt-args
Arguments for `fmt'.
descr
Error description. If there are no additional information, it is
`#f'. Otherwise it is a list of 5 elements which describes the
error and its location in the input stream:
0. Error code (number).
1. Line number (starts at 1).
2. Column number (starts at 0).
3. Context in which the error occurred, i.e. a part of the input
text which was found to contain the error.
4. Offset of point that caused the error within the context.
A special syntax is provided to extract parts of the `descr' list:
-- Gamma Syntax: xml-error-descr descr key
Extract from DESCR the part identified by KEY. Use this macro in
the error handlers. Valid values for KEY are:
-- xml-error-descr key: #:error-code
Return the error code.
-- xml-error-descr key: #:line
Return line number.
-- xml-error-descr key: #:column
Return column number.
-- xml-error-descr key: #:has-context?
Return `#t' if the description has context part. Use the two
keywords below only if
(xml-error-descr d #:has-context?
returned `#t'.
-- xml-error-descr key: #:context
Return context string.
-- xml-error-descr key: #:error-offset
Return the location within `#:context' where the error
occurred.
If no special handler is set, the default `guile' error handler
displays the error and its approximate location on the standard error
port. For example, given the following input file:
$ cat input.xml
the `xmlck.scm' (*note xmlck.scm::) produces:
$ guile -s examples/xmlck.scm < input.xml
ERROR: In procedure xml-primitive-parse:
ERROR: not well-formed (invalid token) near line 2
To provide a more detailed diagnostics, catch the `gamma-xml-error'
code and use information from the `descr' list. For example:
(catch 'gamma-xml-error
(lambda ()
(xml-parse (xml-make-parser)))
(lambda (key func fmt args descr)
(with-output-to-port
(current-error-port)
(lambda ()
(cond
((not descr)
(apply format #t fmt args)
(newline))
(else
(format #t
"~A:~A: ~A~%"
(xml-error-descr descr #:line)
(xml-error-descr descr #:column)
(xml-error-string (xml-error-descr descr #:error-code)))
(if (xml-error-descr descr #:has-context?)
(let ((ctx-text (xml-error-descr descr #:context))
(ctx-pos (xml-error-descr descr #:error-offset)))
(format #t
"Context (^ marks the point): ~A^~A~%"
(substring ctx-text 0 ctx-pos)
(substring ctx-text ctx-pos))))
(exit 1)))))))
When applied to the same input document as in the previous example,
this code produces:
$ guile -s examples/xml-check.scm < input.xml
2:8: not well-formed (invalid token)
Context (^ marks the point):
4.5 Expat Handlers
==================
This section describes all available element handlers. For clarity,
each handler is described in its own subsection. For each handler, we
indicate a "keyword" that is used when registering this handler and the
"handler prototype".
To register handlers, use `xml-make-parser' or `xml-set-handler'
functions. *Note creating parsers::, for a detailed discussion of
these functions.
4.5.1 start-element-handler
---------------------------
-- Handler Keyword: #:start-element-handler
Sets handler for start (and empty) tags.
The handler must be defined as follows:
-- Handler prototype: start-element name attrs
Arguments:
NAME
Element name.
ATTRS
A list of element attributes. Each attribute is represented
by a cons (`car' holds attribute name, `cdr' holds its value).
4.5.2 end-element-handler
-------------------------
-- Handler Keyword: #:end-element-handler
Sets handler for end (and empty) tags. An empty tag generates a
call to both start and end handlers (in that order).
The handler must be defined as follows:
-- Handler prototype: end-element name
Arguments:
NAME
Element name
4.5.3 character-data-handler
----------------------------
-- Handler Keyword: #:character-data-handler
Sets a text handler. A single block of contiguous text free of
markup may result in a sequence of calls to this handler. So, if
you are searching for a pattern in the text, it may be split
across calls to this handler.
The handler itself is defined as:
-- Handler prototype: character-data text
Arguments:
TEXT
The text.
4.5.4 processing-instruction-handler
------------------------------------
-- Handler Keyword: #:processing-instruction-handler
Set a handler for "processing instructions".
-- Handler prototype: processing-instruction target data
Arguments are:
TARGET
First word in the processing instruction.
DATA
The rest of the characters in the processing instruction,
after TARGET and whitespace following it.
4.5.5 comment-handler
---------------------
-- Handler Keyword: #:comment-handler
Sets a handler for comments.
-- Handler prototype: comment text
TEXT
The text inside the comment delimiters.
4.5.6 start-cdata-section-handler
---------------------------------
-- Handler Keyword: #:start-cdata-section-handler
Sets a handler that gets called at the beginning of a CDATA
section.
The handler is defined as follows:
-- Handler prototype: start-cdata-section
4.5.7 end-cdata-section-handler
-------------------------------
-- Handler Keyword: #:end-cdata-section-handler
Sets a handler that gets called at the end of a CDATA section.
The handler is defined as:
-- Handler prototype: end-cdata-section
4.5.8 default-handler
---------------------
-- Handler Keyword: #:default-handler
Sets a handler for any characters in the document which wouldn't
otherwise be handled. This includes both data for which no
handlers can be set (like some kinds of DTD declarations) and data
which could be reported but which currently has no handler set.
-- Handler prototype: default text
TEXT
A string containing all non-handled characters, which are
passed exactly as they were present in the input XML document
except that they will be encoded in UTF-8 or UTF-16. Line
boundaries are not normalized. Note that a byte order mark
character is not passed to the default handler. There are no
guarantees about how characters are divided between calls to
the default handler: for example, a comment might be split
between multiple calls. Setting the `default' handler has
the side effect of turning off expansion of references to
internally defined general entities. Such references are
passed to the default handler verbatim.
4.5.9 default-handler-expand
----------------------------
-- Handler Keyword: #:default-handler-expand
This sets a default handler as above, but does not inhibit the
expansion of internal entity references. Any entity references
are not passed to the handler.
The handler prototype is the same as in *note default-handler::.
4.5.10 skipped-entity-handler
-----------------------------
-- Handler Keyword: #:skipped-entity-handler
Set a skipped entity handler, i.e. a handler which is called if:
* An entity reference is encountered for which no declaration
has been read and this is not an error.
* An internal entity reference is read, but not expanded,
because a `#:default-handler' has been set.
-- Handler prototype: skipped-entity entity-name parameter?
Arguments are:
ENTITY-NAME
Name of the entity.
PARAMETER?
This argument is `#t' if the entity is a parameter, and `#f'
otherwise.
4.5.11 start-namespace-decl-handler
-----------------------------------
-- Handler Keyword: #:start-namespace-decl-handler
Set a handler to be called when a namespace is declared.
-- Handler prototype: start-namespace-decl prefix uri
Arguments:
PREFIX
Namespace prefix.
URI
Namespace URI.
4.5.12 end-namespace-decl-handler
---------------------------------
-- Handler Keyword: #:end-namespace-decl-handler
Set a handler to be called when leaving the scope of a namespace
declaration. This will be called, for each namespace declaration,
after the handler for the end tag of the element in which the
namespace was declared.
The handler prototype is:
-- Handler prototype: end-namespace-decl prefix
4.5.13 xml-decl-handler
-----------------------
-- Handler Keyword: #:xml-decl-handler
Sets a handler that is called for XML declarations and also for
text declarations discovered in external entities.
-- Handler prototype: xml-decl version encoding . detail
Arguments:
VERSION
Version specification (string), or `#f', for text
declarations.
ENCODING
Encoding. May be `#f'.
DETAIL
`Unspecified', if there was no standalone parameter in the
declaration. Otherwise, `#t' or `#f' depending on whether it
was given as `yes' or `no'.
4.5.14 start-doctype-decl-handler
---------------------------------
-- Handler Keyword: #:start-doctype-decl-handler
Set a handler that is called at the start of a `DOCTYPE'
declaration, before any external or internal subset is parsed.
-- Handler prototype: start-doctype-decl name sysid pubid
has-internal-subset?
Arguments:
NAME
Declaration name.
SYSID
System ID. May be `#f'.
PUBID
Public ID. May be `#f'.
HAS-INTERNAL-SUBSET?
`#t' if the `DOCTYPE' declaration has an internal subset,
`#f' otherwise.
4.5.15 end-doctype-decl-handler
-------------------------------
-- Handler Keyword: #:end-doctype-decl-handler
Set a handler that is called at the end of a `DOCTYPE'
declaration, after parsing any external subset.
The handler takes no arguments:
-- Handler prototype: end-doctype-decl
4.5.16 attlist-decl-handler
---------------------------
-- Handler Keyword: #:attlist-decl-handler
Sets a handler for `attlist' declarations in the DTD. This
handler is called for each attribute, which means, in particular,
that a single attlist declaration with multiple attributes causes
multiple calls to this handler.
The handler prototype is:
-- Handler prototype: attlist-decl el-name att-name att-type detail
Argument:
EL-NAME
Name of the element for which the attribute is being declared.
ATT-NAME
Attribute name.
DETAIL
Default value, if EL-NAME is a `#FIXED' attribute, `#t', if
it is a `#REQUIRED' attribute, and `#f', if it is a
`#IMPLIED' attribute.
4.5.17 entity-decl-handler
--------------------------
-- Handler Keyword: #:entity-decl-handler
Sets a handler that will be called for all entity declarations.
-- Handler prototype: entity-decl name param? value base sys-id pub-id
notation
Arguments:
NAME
Entity name.
PARAM?
For parameter entities, `#t'. Otherwise, `#f'.
VALUE
For internal entities, entity value. Otherwise, `#f'.
BASE
Base.
SYS-ID
System ID. For internal entities - `#f'.
PUB-ID
Public ID. For internal entities - `#f'.
NOTATION
Notation name, for unparsed entity declarations. Otherwise,
`#f'. Unparsed are entity declarations that have a notation
(`NDATA') field, such as:
4.5.18 notation-decl-handler
----------------------------
-- Handler Keyword: #:notation-decl-handler
Sets a handler that receives notation declarations.
Handler prototype is:
-- Handler prototype: notation-decl notation-name base system-id
public-id
4.5.19 not-standalone-handler
-----------------------------
-- Handler Keyword: #:not-standalone-handler
Sets a handler that is called if the document is not "standalone",
i.e. when there is an external subset or a reference to a
parameter entity, but does not have `standalone' set to "yes" in
an XML declaration.
The handler takes no arguments:
-- Handler prototype: not-standalone
4.6 miscellaneous functions
===========================
-- Scheme function: xml-expat-version-string
Return the version of the expat library as a string.
For example:
(xml-expat-version-string) => "expat_2.0.1"
-- Scheme function: xml-expat-version
Return the version of the expat library as a triplet: `(major
minor micro)'.
For example:
(xml-expat-version) => (2 0 1)
-- Scheme function: xml-default-current
Pass current markup to the default handler (*note
default-handler::). This function may be called only from a
callback handler.
-- Scheme function: xml-error-string code)
Return a textual description corresponding to the CODE argument.
*Note catching gamma-xml-error::, for an example of using this
function.
-- Scheme function: xml-current-line-number parser
Return number of the current input line in PARSER. Input lines
are numbered from `1'.
-- Scheme function: xml-current-column-number parser
Return number of column in the current input line.
-- Scheme function: xml-current-byte-count parser
Return the number of bytes in the current event. Returns `0' if
the event is inside a reference to an internal entity and for the
end-tag event for empty element tags (the later can be used to
distinguish empty-element tags from empty elements using separate
start and end tags).
5 How to Report a Bug
*********************
If you think you've found a bug, please report it to
. Be sure to include maximum information needed
to reliably reproduce it, or at least to analyze it. The information
needed is:
* Version of the package you are using.
* Compilation options used when configuring the package.
* Run-time configuration.
* Conditions under which the bug appears.
Appendix A GNU Free Documentation License
*****************************************
Version 1.2, November 2002
Copyright (C) 2000,2001,2002 Free Software Foundation, Inc.
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Concept Index
*************
This is a general index of all issues discussed in this manual
attlist declaration handler: See 4.5.16. (line 922)
attlist-decl: See 4.5.16. (line 931)
callback, expat: See 4.1. (line 336)
callbacks, expat: See 4.5. (line 673)
character data handler: See 4.5.3. (line 718)
character-data: See 4.5.3. (line 727)
closelog: See 2. (line 188)
comment: See 4.5.5. (line 755)
config file, MySQL: See 3. (line 244)
connection to SQL, closing: See 3. (line 252)
connection to SQL, opening: See 3. (line 201)
default: See 4.5.8. (line 789)
default handler: See 4.5.8. (line 782)
default handler, with expansion: See 4.5.9. (line 805)
end cdata section handler: See 4.5.7. (line 772)
end doctype declaration handler: See 4.5.15. (line 911)
end element handler: See 4.5.2. (line 703)
end namespace declaration handler: See 4.5.12. (line 852)
end-cdata-section: See 4.5.7. (line 778)
end-doctype-decl: See 4.5.15. (line 918)
end-element: See 4.5.2. (line 710)
end-namespace-decl: See 4.5.12. (line 861)
entity declaration handler: See 4.5.17. (line 947)
entity-decl: See 4.5.17. (line 952)
error handling, XML: See 4.4. (line 545)
Expat: See 4. (line 325)
expat, basics: See 4.1. (line 336)
facility, syslog: See 2. (line 110)
FDL, GNU Free Documentation License: See Appendix A.
(line 1064)
handler, attlist declaration: See 4.5.16. (line 922)
handler, character data: See 4.5.3. (line 718)
handler, default: See 4.5.8. (line 782)
handler, default, with expansion: See 4.5.9. (line 805)
handler, end cdata section: See 4.5.7. (line 772)
handler, end doctype declaration: See 4.5.15. (line 911)
handler, end element: See 4.5.2. (line 703)
handler, end namespace declaration: See 4.5.12. (line 852)
handler, entity declaration: See 4.5.17. (line 947)
handler, not standalone document: See 4.5.19. (line 994)
handler, notation declaration: See 4.5.18. (line 983)
handler, processing instruction: See 4.5.4. (line 735)
handler, skipped entity: See 4.5.10. (line 815)
handler, start cdata section: See 4.5.6. (line 761)
handler, start doctype declaration: See 4.5.14. (line 887)
handler, start element: See 4.5.1. (line 685)
handler, start namespace declaration: See 4.5.11. (line 837)
handler, XML declaration: See 4.5.13. (line 865)
handlers, expat <1>: See 4.5. (line 673)
handlers, expat: See 4.1. (line 336)
libexpat: See 4. (line 325)
LOG_ALERT: See 2. (line 146)
LOG_AUTH: See 2. (line 114)
LOG_AUTHPRIV: See 2. (line 116)
LOG_CONS: See 2. (line 86)
LOG_CRIT: See 2. (line 147)
LOG_CRON: See 2. (line 117)
LOG_DAEMON: See 2. (line 118)
LOG_DEBUG: See 2. (line 152)
LOG_EMERG: See 2. (line 144)
LOG_ERR: See 2. (line 148)
LOG_FTP: See 2. (line 119)
LOG_INFO: See 2. (line 151)
LOG_LOCAL0: See 2. (line 121)
LOG_LOCAL1: See 2. (line 121)
LOG_LOCAL2: See 2. (line 121)
LOG_LOCAL3: See 2. (line 121)
LOG_LOCAL4: See 2. (line 121)
LOG_LOCAL5: See 2. (line 121)
LOG_LOCAL6: See 2. (line 121)
LOG_LOCAL7: See 2. (line 121)
LOG_LPR: See 2. (line 122)
LOG_MAIL: See 2. (line 124)
LOG_NDELAY: See 2. (line 90)
LOG_NEWS: See 2. (line 125)
LOG_NOTICE: See 2. (line 150)
LOG_NOWAIT: See 2. (line 94)
LOG_ODELAY: See 2. (line 98)
LOG_PERROR: See 2. (line 103)
LOG_PID: See 2. (line 107)
LOG_SYSLOG: See 2. (line 126)
LOG_USER: See 2. (line 127)
LOG_UUCP: See 2. (line 128)
LOG_WARNING: See 2. (line 149)
MySQL: See 3. (line 193)
not standalone document handler: See 4.5.19. (line 994)
not-standalone: See 4.5.19. (line 1003)
notation declaration handler: See 4.5.18. (line 983)
notation-decl: See 4.5.18. (line 990)
open-syslog-port: See 2. (line 171)
openlog: See 2. (line 75)
openlog?: See 2. (line 185)
option file, MySQL: See 3. (line 244)
parser, creating: See 4.1. (line 344)
parsers, XML, creating: See 4.2. (line 429)
PostgreSQL: See 3. (line 193)
priority, syslog: See 2. (line 144)
processing instruction handler: See 4.5.4. (line 735)
processing-instruction: See 4.5.4. (line 739)
query, SQL: See 3. (line 256)
skipped entity handler: See 4.5.10. (line 815)
skipped-entity: See 4.5.10. (line 825)
SQL: See 3. (line 193)
sql-catch-failure: See 3. (line 275)
sql-close-connection: See 3. (line 252)
sql-ignore-failure: See 3. (line 316)
sql-open-connection: See 3. (line 201)
sql-query: See 3. (line 256)
SSL, using with SQL: See 3. (line 237)
start cdata section handler: See 4.5.6. (line 761)
start doctype declaration handler: See 4.5.14. (line 887)
start element handler: See 4.5.1. (line 685)
start namespace declaration handler: See 4.5.11. (line 837)
start-cdata-section: See 4.5.6. (line 768)
start-doctype-decl: See 4.5.14. (line 893)
start-element: See 4.5.1. (line 691)
start-namespace-decl: See 4.5.11. (line 841)
syslog: See 2. (line 70)
syslog facility: See 2. (line 110)
syslog priority: See 2. (line 144)
syslog-tag: See 2. (line 137)
XML: See 4. (line 325)
XML declaration handler: See 4.5.13. (line 865)
xml error handling: See 4.4. (line 545)
xml-current-byte-count: See 4.6. (line 1039)
xml-current-column-number: See 4.6. (line 1036)
xml-current-line-number: See 4.6. (line 1032)
xml-decl: See 4.5.13. (line 870)
xml-default-current: See 4.6. (line 1022)
xml-error-descr: See 4.4. (line 591)
xml-error-string: See 4.6. (line 1027)
xml-expat-version: See 4.6. (line 1015)
xml-expat-version-string: See 4.6. (line 1008)
xml-make-parser: See 4.2. (line 492)
xml-parse: See 4.3. (line 539)
xml-parse-more: See 4.3. (line 529)
xml-primitive-make-parser: See 4.2. (line 437)
xml-primitive-parse: See 4.3. (line 515)
xml-primitive-set-handler: See 4.2. (line 466)
xml-set-encoding: See 4.2. (line 445)
xml-set-handler: See 4.2. (line 483)
xmlck.scm, example: See 4.1. (line 354)