diff options
Diffstat (limited to 'lib/kernel/doc/src/error_logger.xml')
| -rw-r--r-- | lib/kernel/doc/src/error_logger.xml | 65 |
1 files changed, 48 insertions, 17 deletions
diff --git a/lib/kernel/doc/src/error_logger.xml b/lib/kernel/doc/src/error_logger.xml index a8273e59e2..91bf57cb91 100644 --- a/lib/kernel/doc/src/error_logger.xml +++ b/lib/kernel/doc/src/error_logger.xml @@ -4,7 +4,7 @@ <erlref> <header> <copyright> - <year>1996</year><year>2016</year> + <year>1996</year><year>2017</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> @@ -33,7 +33,7 @@ <description> <p>The Erlang <em>error logger</em> is an event manager (see <seealso marker="doc/design_principles:des_princ">OTP Design Principles</seealso> and - <seealso marker="stdlib:gen_event"><c>stdlib:gen_event(3)</c></seealso>), + <seealso marker="stdlib:gen_event"><c>gen_event(3)</c></seealso>), registered as <c>error_logger</c>. Errors, warnings, and info events are sent to the error logger from the Erlang runtime system and the different Erlang/OTP applications. The events are, by default, @@ -44,12 +44,12 @@ executing.</p> <p>Initially, <c>error_logger</c> has only a primitive event handler, which buffers and prints the raw event messages. During - system startup, the <c>Kernel</c> application replaces this with a + system startup, the Kernel application replaces this with a <em>standard event handler</em>, by default one that writes - nicely formatted output to the terminal. <c>Kernel</c> can also be + nicely formatted output to the terminal. Kernel can also be configured so that events are logged to a file instead, or not logged at all, see <seealso marker="kernel_app"><c>kernel(6)</c></seealso>.</p> - <p>Also the <c>SASL</c> application, if started, adds its own event + <p>Also the SASL application, if started, adds its own event handler, which by default writes supervisor, crash, and progress reports to the terminal. See <seealso marker="sasl:sasl_app"><c>sasl(6)</c></seealso>.</p> @@ -58,9 +58,9 @@ User-defined event handlers can be added to handle application-specific events, see <seealso marker="#add_report_handler/1"><c>add_report_handler/1,2</c></seealso>. - Also, a useful event handler is provided in <c>STDLIB</c> for multi-file + Also, a useful event handler is provided in STDLIB for multi-file logging of events, see - <seealso marker="stdlib:log_mf_h"><c>stdlib:log_mf_h(3)</c></seealso>.</p> + <seealso marker="stdlib:log_mf_h"><c>log_mf_h(3)</c></seealso>.</p> <p>Warning events were introduced in Erlang/OTP R9C and are enabled by default as from Erlang/OTP 18.0. To retain backwards compatibility with existing user-defined event handlers, the warning events can be @@ -82,7 +82,7 @@ <p>Adds a new event handler to the error logger. The event handler must be implemented as a <c>gen_event</c> callback module, see - <seealso marker="stdlib:gen_event"><c>stdlib:gen_event(3)</c></seealso>.</p> + <seealso marker="stdlib:gen_event"><c>gen_event(3)</c></seealso>.</p> <p><c><anno>Handler</anno></c> is typically the name of the callback module and <c><anno>Args</anno></c> is an optional term (defaults to []) passed to the initialization callback function <c><anno>Handler</anno>:init/1</c>. @@ -97,7 +97,7 @@ <desc> <p>Deletes an event handler from the error logger by calling <c>gen_event:delete_handler(error_logger, <anno>Handler</anno>, [])</c>, - see <seealso marker="stdlib:gen_event"><c>stdlib:gen_event(3)</c></seealso>.</p> + see <seealso marker="stdlib:gen_event"><c>gen_event(3)</c></seealso>.</p> </desc> </func> <func> @@ -110,7 +110,7 @@ The <c><anno>Format</anno></c> and <c><anno>Data</anno></c> arguments are the same as the arguments of <seealso marker="stdlib:io#format/2"><c>io:format/2</c></seealso> - in <c>STDLIB</c>. + in STDLIB. The event is handled by the standard event handler.</p> <p><em>Example:</em></p> <pre> @@ -126,6 +126,12 @@ ok</pre> <seealso marker="#error_report/1"><c>error_report/1</c></seealso> instead.</p> </warning> + <warning> + <p>If the Unicode translation modifier (<c>t</c>) is used in + the format string, all error handlers must ensure that the + formatted output is correctly encoded for the I/O + device.</p> + </warning> </desc> </func> <func> @@ -163,6 +169,19 @@ ok</pre> </desc> </func> <func> + <name name="get_format_depth" arity="0"/> + <fsummary>Get the value of the Kernel application variable + <c>error_logger_format_depth</c>.</fsummary> + <desc> + <p>Returns <c>max(10, Depth)</c>, where <c>Depth</c> is the + value of + <seealso marker="kernel:kernel_app#error_logger_format_depth"> + error_logger_format_depth</seealso> + in the Kernel application, if Depth is an integer. Otherwise, + <c>unlimited</c> is returned.</p> + </desc> + </func> + <func> <name name="info_msg" arity="1"/> <name name="info_msg" arity="2"/> <fsummary>Send a standard information event to the error logger.</fsummary> @@ -171,7 +190,7 @@ ok</pre> The <c><anno>Format</anno></c> and <c><anno>Data</anno></c> arguments are the same as the arguments of <seealso marker="stdlib:io#format/2"><c>io:format/2</c></seealso> - in <c>STDLIB</c>. The event is handled by the standard event handler.</p> + in STDLIB. The event is handled by the standard event handler.</p> <p><em>Example:</em></p> <pre> 1> <input>error_logger:info_msg("Something happened in ~p~n", [a_module]).</input> @@ -184,6 +203,12 @@ ok</pre> the standard event handler, meaning no further events are logged. When in doubt, use <c>info_report/1</c> instead.</p> </warning> + <warning> + <p>If the Unicode translation modifier (<c>t</c>) is used in + the format string, all error handlers must ensure that the + formatted output is correctly encoded for the I/O + device.</p> + </warning> </desc> </func> <func> @@ -235,7 +260,7 @@ ok</pre> <p>Enables or disables printout of standard events to a file.</p> <p>This is done by adding or deleting the standard event handler for output to file. Thus, calling this function overrides - the value of the <c>Kernel</c> <c>error_logger</c> configuration + the value of the Kernel <c>error_logger</c> configuration parameter.</p> <p>Enabling file logging can be used together with calling <c>tty(false)</c>, to have a silent system where @@ -249,7 +274,7 @@ ok</pre> successful, or <c>{error, allready_have_logfile}</c> if logging to file is already enabled, or an error tuple if another error occurred (for example, if <c><anno>Filename</anno></c> - cannot be opened).</p> + cannot be opened). The file is opened with encoding UTF-8.</p> </item> <tag><c>close</c></tag> <item> @@ -274,7 +299,7 @@ ok</pre> to the terminal.</p> <p>This is done by adding or deleting the standard event handler for output to the terminal. Thus, calling this function overrides - the value of the <c>Kernel</c> <c>error_logger</c> configuration parameter.</p> + the value of the Kernel <c>error_logger</c> configuration parameter.</p> </desc> </func> <func> @@ -323,7 +348,7 @@ ok</pre> The <c><anno>Format</anno></c> and <c><anno>Data</anno></c> arguments are the same as the arguments of <seealso marker="stdlib:io#format/2"><c>io:format/2</c></seealso> - in <c>STDLIB</c>. + in STDLIB. The event is handled by the standard event handler. It is tagged as an error, warning, or info, see <seealso marker="#warning_map/0"><c>warning_map/0</c></seealso>.</p> @@ -332,6 +357,12 @@ ok</pre> the standard event handler, meaning no further events are logged. When in doubt, use <c>warning_report/1</c> instead.</p> </warning> + <warning> + <p>If the Unicode translation modifier (<c>t</c>) is used in + the format string, all error handlers must ensure that the + formatted output is correctly encoded for the I/O + device.</p> + </warning> </desc> </func> <func> @@ -416,8 +447,8 @@ ok</pre> </section> <section> <title>See Also</title> - <p><seealso marker="stdlib:gen_event"><c>stdlib:gen_event(3)</c></seealso>, - <seealso marker="stdlib:log_mf_h"><c>stdlib:log_mf_h(3)</c></seealso> + <p><seealso marker="stdlib:gen_event"><c>gen_event(3)</c></seealso>, + <seealso marker="stdlib:log_mf_h"><c>log_mf_h(3)</c></seealso> <seealso marker="kernel_app"><c>kernel(6)</c></seealso> <seealso marker="sasl:sasl_app"><c>sasl(6)</c></seealso></p> </section> |