6 files changed, 176 insertions, 225 deletions

diff --git a/docs/ref/api/log/index.md b/docs/ref/api/log/index.md
deleted file mode 100644
index b51bbe3b..00000000
--- a/docs/ref/api/log/index.md
+++ /dev/null
@@ -1,9 +0,0 @@
-# Logging
-
-These interfaces deal with message logs, which can be submitted
-by the application or by NNG itself.
-
-- [nng_log](./nng_log.md) --- Message logs
-- [nng_log_facility](./nng_log_facility.md) --- Facility for message logs
-- [nng_log_level](./nng_log_level.md) --- Severity level for message logs
-- [nng_log_logger](./nng_log_logger.md) --- Handler for log messages
diff --git a/docs/ref/api/log/nng_log.md b/docs/ref/api/log/nng_log.md
deleted file mode 100644
index 5d0db5a9..00000000
--- a/docs/ref/api/log/nng_log.md
+++ /dev/null
@@ -1,75 +0,0 @@
-# nng_log
-
-## NAME
-
-# nng_log --- log messages
-
-## SYNOPSIS
-
-```c
-#include <nng/nng.h>
-
-void nng_log_err(const char *msgid, const char *msg, ...);
-void nng_log_warn(const char *msgid, const char *msg, ...);
-void nng_log_notice(const char *msgid, const char *msg, ...);
-void nng_log_info(const char *msgid, const char *msg, ...);
-void nng_log_debug(const char *msgid, const char *msg, ...);
-
-void nng_log_auth(nng_log_level level, const char *msgid, const char *msg, ...);
-```
-
-## DESCRIPTION
-
-The {{i:`nng_log`}} functions are used to post a message to system or application {{i:logs}}.
-
-The first five forms all post a message at the severity indicated by the function name.
-The _msgid_ should be a short message identifier that should indicate the message in question.
-A `NULL` value for _msgid_ can be used as well.
-
-Message identifiers can be used to assist in filtering and classifying logged messages.
-These should uniquely identify the nature of the problem, whe possible, to assist in trouble-shooting.
-They should also be short.
-Eight characters or less is ideal, and more than sixteen is strongly discouraged.
-Message identifiers may not be displayed to human readers, or may not be displayed by default.
-Therefore, any information in the message identifier should also be in the log content.
-
-The message is formatted as if by `sprintf`, using `msg` as the format, and remaining arguments as arguments to the format.
-
-The final function, {{i:`nng_log_auth`}}, is used for posting authentication related messages which might be treated specially,
-such as be storing them in a separate (and presumably more secure) log file.
-It takes the severity as a level in _level_.
-The severity can be one of the following values:
-
-- `NNG_LOG_ERR`
-- `NNG_LOG_WARN`
-- `NNG_LOG_NOTICE`
-- `NNG_LOG_INFO`
-- `NNG_LOG_DEBUG`
-
-The message itself is handled according to the logging facility set up with [`nng_log_set_logger`][log_logger].
-Message delivery is best effort, and messages may be suppressed based on the priority set with [`nng_log_set_level`][log_level].
-
-Note that in order to get log messages, a suitable logger must be set using {{i:`nng_log_set_logger`}}.
-The default logger, {{i:`nng_null_logger`}} simply discards logged content.
-
-> [!TIP]
-> Applications should take care to limit the use of higher severity levels, as message logs
-> are potentially expensive, increase stress for end users and administrators, and further may
-> mask real problems if incorrectly over used.
->
-> Warnings and error messages should be concise and actionable, and notices should only
-> really be those things that are worthy of attention.
->
-> Informational and debug messages used during development should be removed when no longer
-> needed, as these messages can overwhelm logging subsystems and can reduce the
-> signal-to-noise value for the message logs, impairing the diagnostic value of the logs.
-
-## SEE ALSO
-
-[nng_log_facility][log_facility],
-[nng_log_level][log_level],
-[nng_log_logger][log_logger]
-
-[log_facility]: ./nng_log_facility.md
-[log_level]: ./nng_log_level.md
-[log_logger]: ./nng_log_logger.md
diff --git a/docs/ref/api/log/nng_log_facility.md b/docs/ref/api/log/nng_log_facility.md
deleted file mode 100644
index 28ffd05f..00000000
--- a/docs/ref/api/log/nng_log_facility.md
+++ /dev/null
@@ -1,47 +0,0 @@
-# nng_log_facility
-
-## NAME
-
-nng_log_facility --- facility or category for log messages
-
-## SYNOPSIS
-
-```c
-#include <nng/nng.h>
-
-typedef enum nng_log_facility {
-	NNG_LOG_USER   = 1,
-	NNG_LOG_DAEMON = 3,
-	NNG_LOG_AUTH   = 10,
-	NNG_LOG_LOCAL0 = 16,
-	NNG_LOG_LOCAL1 = 17,
-	NNG_LOG_LOCAL2 = 18,
-	NNG_LOG_LOCAL3 = 19,
-	NNG_LOG_LOCAL4 = 20,
-	NNG_LOG_LOCAL5 = 21,
-	NNG_LOG_LOCAL6 = 22,
-	NNG_LOG_LOCAL7 = 23,
-} nng_log_facility;
-
-void nng_log_set_facility(nng_log_facility facility);
-```
-
-## DESCRIPTION
-
-An {{i:`nng_log_facility`}} object represents a facility, which can be thought of as
-a category, for log message. Normally these are used to identify the source of the
-message. The facility values here correspond to those typical used with the UNIX
-`syslog` logging system.
-
-The `nng_log_set_facility` is used to set the _facility_ of the application posting logs,
-so that messages that are submitted by the application can be correctly attributed to
-the application itself. It may also help in message routing.
-
-Note that while the log levels used here overlap with common levels used by the
-`syslog` system found on POSIX systems, applications should not the numeric values
-being the same.
-
-## SEE ALSO
-
-[nng_log](./nng_log.md),
-[nng_log_level](./nng_log_level.md)
diff --git a/docs/ref/api/log/nng_log_level.md b/docs/ref/api/log/nng_log_level.md
deleted file mode 100644
index 7e7cadb2..00000000
--- a/docs/ref/api/log/nng_log_level.md
+++ /dev/null
@@ -1,47 +0,0 @@
-# nng_log_level
-
-## NAME
-
-nng_log_level --- severity level for logging messages
-
-## SYNOPSIS
-
-```c
-#include <nng/nng.h>
-
-typedef enum nng_log_level {
-	NNG_LOG_NONE   = 0, // used for filters only, NNG suppresses these
-	NNG_LOG_ERR    = 3,
-	NNG_LOG_WARN   = 4,
-	NNG_LOG_NOTICE = 5,
-	NNG_LOG_INFO   = 6,
-	NNG_LOG_DEBUG  = 7
-} nng_log_level;
-
-void nng_log_set_level(nng_log_level level);
-nng_log_level nng_log_get_level(void);
-```
-
-## DESCRIPTION
-
-The `nng_log_level` type represents a severity for logged messages.
-These levels correspond to those found in the UNIX `syslog` subsystem,
-although applications should not depend upon the values being identical.
-
-The `nng_log_set_level` function is used to set the minimum severity to _level_ for processing log messages.
-Any messages with a less severe rating are not processed and simply are discarded.
-Use `NNG_LOG_NONE` to suppress all log messages.
-Use `NNG_LOG_DEBUG` to receive all log messages.
-
-The `nng_log_get_level` function returns the current log level, which can be useful
-to elide processing to create log content that will simply be discarded anyway.
-
-## RETURN VALUES
-
-The `nng_log_get_level` functions returns the current log level.
-
-## SEE ALSO
-
-[nng_log](./nng_log.md),
-[nng_log_facility](./nng_log_facility.md),
-[nng_log_logger](./nng_log_logger.md)
diff --git a/docs/ref/api/log/nng_log_logger.md b/docs/ref/api/log/nng_log_logger.md
deleted file mode 100644
index 26551091..00000000
--- a/docs/ref/api/log/nng_log_logger.md
+++ /dev/null
@@ -1,47 +0,0 @@
-# nng_log_logger
-
-## NAME
-
-nng_log_logger --- logging handler
-
-## SYNOPSIS
-
-```c
-#include <nng/nng.h>
-
-typedef void (*nng_logger)(nng_log_level level, nng_log_facility facility,
-    const char *msgid, const char *msg);
-
-void nng_null_logger(nng_log_level, nng_log_facility, const char *, const char *);
-void nng_stderr_logger(nng_log_level, nng_log_facility, const char *, const char *);
-void nng_system_logger(nng_log_level, nng_log_facility, const char *, const char *);
-
-void nng_log_set_logger(nng_logger logger);
-```
-
-## DESCRIPTION
-
-An {{i:`nng_logger`}}{{hi:logger}} is a function used as a handler to process logged messages.
-This is responsible for the final disposition of the logged messages.
-
-The {{i:`nng_log_set_logger`}} function is used to set the base logging function to _logger_.
-The _logger_ may be a user defined function to process log messages.
-Only a single logger may be registered at a time.
-If needed, the logger should make copies of either _msgid_ or _msg_, as they will not be valid after the logger returns.
-
-The {{i:`nng_null_logger`}} function is an implementation of `nng_logger` that simply discards the content.
-This is the default logger, so logging is disabled by default.
-
-The {{i:`nng_stderr_logger`}} function is an implementation that logs messages to the standard error stream.
-It will attempt to colorize messages by the severity, if the standard error is a terminal device.
-This can be supressed by setting either the `NO_COLOR` or `NNG_LOG_NO_COLOR` environment variables.
-
-The {{i:`nng_system_logger`}} attempts to use an appropriate system facility to log messages.
-For POSIX systems, this means using `syslog` to process the messages.
-For other systems the defauilt behavior may be the same as `nng_stderr_logger`.
-
-## SEE ALSO
-
-[nng_log](./nng_log.md),
-[nng_log_facility](./nng_log_facility.md),
-[nng_log_level](./nng_log_level.md)
diff --git a/docs/ref/api/logging.md b/docs/ref/api/logging.md
new file mode 100644
index 00000000..cbed636c
--- /dev/null
+++ b/docs/ref/api/logging.md
@@ -0,0 +1,176 @@
+# Logging
+
+This chapter describes the support for message logs.
+Both applications and _NNG_ itself can emit logs, which can be useful
+for application field support and debugging. Additionally applications
+can customize the handling of this logging as needed.
+
+Note that logging is disabled by default unless an application
+configures a suitable logger with [`nng_log_set_logger`][log_logger].
+
+## Submitting Logs
+
+```c
+void nng_log_err(const char *msgid, const char *msg, ...);
+void nng_log_warn(const char *msgid, const char *msg, ...);
+void nng_log_notice(const char *msgid, const char *msg, ...);
+void nng_log_info(const char *msgid, const char *msg, ...);
+void nng_log_debug(const char *msgid, const char *msg, ...);
+```
+
+These {{hi:`nng_log`}} functions inject a a message into the
+logging system, where it will be processed and potentially go to
+system logs, standard output, or procssed further.
+
+The _msgid_ is a short prefix that should uniquely identify the message,
+possibly also with some kind of category. It is recommended that
+strings between 8 and 16 charactes be used. As this may, but will not necessarily
+be displayed to the user, the content of the message should not appear
+solely in this field. A `NULL` value is permitted here, but that may
+make filtering the message or other automatic processing more difficult.
+
+The _msg_ is a `printf`-style format string, which is used to format the
+message content. The following arguments are consumed in the
+same manner as `printf`.
+
+> [!TIP]
+> Applications should take care to limit the use of higher severity levels, as message logs
+> are potentially expensive, increase stress for end users and administrators, and further may
+> mask real problems if incorrectly over used.
+>
+> Warnings and error messages should be concise and actionable, and notices should only
+> really be those things that are worthy of attention.
+>
+> Informational and debug messages used during development should be removed when no longer
+> needed, as these messages can overwhelm logging subsystems and can reduce the
+> signal-to-noise value for the message logs, impairing the diagnostic value of the logs.
+
+## Auth Logs
+
+```c
+void nng_log_auth(nng_log_level level, const char *msgid, const char *msg, ...);
+```
+
+The {{i:`nng_log_auth`}} function formats and injects a security related log message.
+("Auth" can indicate either "authentication" or "authorization".)
+The _level_ is a [log level][log_level].
+The _msgid_, _msg_, and any remaining arguments are processed in a fashion
+similar to the other [logging functions][submitting_logs], except that the
+logs may be are logged using the `NNG_LOG_AUTH` [facility][log_facility], and thus may be
+redirected or receive other special treatment.
+
+## Log Levels
+
+```c
+typedef enum nng_log_level nng_log_level;
+
+void nng_log_set_level(nng_log_level level);
+nng_log_level nng_log_get_level(void);
+```
+
+The {{i:`nng_log_level`}} type represents a severity for logged messages.
+These levels correspond to those found in the UNIX syslog subsystem,
+although applications should not depend upon the values being identical.
+
+The {{i:`nng_log_set_level`}} function sets the log level.
+Messages with a severity that is numerically greater than this (less-severe)
+will be discarded.
+
+The {{i:`nng_log_get_level`}} function returns the log level most recently
+set by `nng_log_set_level` or the default
+if that function has not been called.
+
+The log levels are defined as follows:
+
+```c
+typedef enum nng_log_level {
+	NNG_LOG_NONE   = 0, // used for filters only, NNG suppresses these
+	NNG_LOG_ERR    = 3,
+	NNG_LOG_WARN   = 4,
+	NNG_LOG_NOTICE = 5,
+	NNG_LOG_INFO   = 6,
+	NNG_LOG_DEBUG  = 7
+} nng_log_level;
+```
+
+The value `NNG_LOG_NONE` may be useful to suppress message logs altogether.
+
+The default level is typically `NNG_LOG_NOTICE`, but applications should
+select a value rather than relying upon the default.
+
+## Log Facilities
+
+```c
+typedef enum nng_log_facility
+
+void nng_log_set_facility(nng_log_facility facility);
+```
+
+Logging facilities are used to indicate the source of a log message,
+and may be useful in routing and processing these logs.
+Traditionally these are used with the UNIX `syslog` system, and
+the values here represent some (but not all) of the values found there.
+
+The following values are defined:
+
+```c
+typedef enum nng_log_facility {
+	NNG_LOG_USER   = 1,
+	NNG_LOG_DAEMON = 3,
+	NNG_LOG_AUTH   = 10,
+	NNG_LOG_LOCAL0 = 16,
+	NNG_LOG_LOCAL1 = 17,
+	NNG_LOG_LOCAL2 = 18,
+	NNG_LOG_LOCAL3 = 19,
+	NNG_LOG_LOCAL4 = 20,
+	NNG_LOG_LOCAL5 = 21,
+	NNG_LOG_LOCAL6 = 22,
+	NNG_LOG_LOCAL7 = 23,
+} nng_log_facility;
+```
+
+The {{i:`nng_log_set_facility`}} function can be used to
+set the facility that the application will use when emitting log
+messages. This should be called as part of initialization of the
+application, if logging is to be used.
+
+The default facility is typically `NNG_LOG_USER`, but applications should
+select a value rather than relying upon the default.
+
+## Log Handlers
+
+```c
+typedef void (*nng_logger)(nng_log_level level, nng_log_facility facility,
+    const char *msgid, const char *msg);
+
+void nng_null_logger(nng_log_level, nng_log_facility, const char *, const char *);
+void nng_stderr_logger(nng_log_level, nng_log_facility, const char *, const char *);
+void nng_system_logger(nng_log_level, nng_log_facility, const char *, const char *);
+
+void nng_log_set_logger(nng_logger logger);
+```
+
+{{i:Log handlers}} are responsible for actually processing the logged messages.
+
+The {{i:`nng_log_set_logger`}} function installs the named _logger_, of type {{i:`nng_logger`}},
+as the log handler. The function _logger_ will be called when any message is meant to
+be processed. (Messages are first filtered by [severity][log_level], then formatted,
+before calling the logger.)
+
+Any previously installed logger is replaced by _logger_.
+
+The {{i:`nng_null_logger`}} function is an implementation of `nng_logger` that simply discards the content.
+This is the default logger, so logging is disabled by default.
+
+The {{i:`nng_stderr_logger`}} function is an implementation that logs messages to the standard error stream.
+It will attempt to colorize messages by the severity, if the standard error is a terminal device.
+This can be suppressed by setting either the `NO_COLOR` or `NNG_LOG_NO_COLOR` environment variables.
+
+The {{i:`nng_system_logger`}} attempts to use an appropriate system facility to log messages.
+For POSIX systems, this means using `syslog` to process the messages.
+For other systems the defauilt behavior may be the same as `nng_stderr_logger`.
+
+[log_level]: #log-levels
+[log_facility]: #log-facilities
+[log_logger]: #log-handlers
+[submitting_logs]: #submitting-logs