boost::logging::writer::named_write< format_write_ > Struct Template Reference

Composed of a named formatter and a named destinations. Thus, you can specify the formatting and destinations as strings. More...

List of all members.

Public Member Functions
void	format (const string_type &format_str)
	sets the format string: what should be before, and what after the original message, separated by "|"
void	format (const string_type &format_before_str, const string_type &format_after_str)
	sets the format strings (what should be before, and what after the original message)
void	destination (const string_type &destination_str)
	sets the destinations string - where should logged messages be outputted
void	write (const string_type &format_str, const string_type &destination_str)
	Specifies the formats and destinations in one step.
template<class destination>
void	replace_destination (const string_type &name, destination d)
	Replaces a destination from the named destination.
template<class formatter>
void	replace_formatter (const string_type &name, formatter d)
	Replaces a formatter from the named formatter.

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Detailed Description

template<class format_write_>
struct boost::logging::writer::named_write< format_write_ >

Composed of a named formatter and a named destinations. Thus, you can specify the formatting and destinations as strings.

#include <boost/logging/format/named_write.hpp>

Contains a very easy interface for using formatters and destinations:

• at construction, specify 2 params: the formatter string and the destinations string

Setting the formatters and destinations to write to is extremely simple:

// Set the formatters (first param) and destinatins (second step) in one step 
g_l()->writer().write("%time%($hh:$mm.$ss.$mili) [%idx%] |\n", "cout file(out.txt) debug");

// set the formatter(s)
g_l()->writer().format("%time%($hh:$mm.$ss.$mili) [%idx%] |\n");

// set the destination(s)
g_l()->writer().destination("cout file(out.txt) debug");

The syntax of the format string

• The format string specifies how the message is to be logged
• Every formatter is escaped using %fmt%
  • Available formatters:
    • "%idx%" - writes the index of the message (formatter::idx)
    • "%time%" - writes the time (formatter::high_precision_time)
    • "%thread_id%" - writes the thread id (formatter::thread_id)
    • if you want to write "%", double it, like this: "%%"
• "|" is used to specify the original message. What is before it, is prepended to the message, what is after, is appended to the message
• If a formatter is configurable, append (params) to it
  • For now, only "%time%" is configurable. For instance, "%time%($hh:$mm.$ss.$mili)" writes time like "21:14.24.674"

Example:

"%time%($hh:$mm.$ss.$mili) [%idx%] |\n"

The output can look like:

21:03.17.243 [1] this is so cool 
21:03.17.243 [2] first error 
21:03.17.243 [3] hello, world

The syntax of the destinations string

• The syntax of the destination string specifies where the message is to be logged
  • Every destination is specified by name
  • Separate destinations by space (' ')
• Available destinations
  • "cout" - writes to std::cout (destination::cout)
  • "cerr" - writes to std::cerr (destination::cerr)
  • "debug" - writes to the debug window: OutputDebugString in Windows, console on Linux (destination::dbg_window)
  • "file" - writes to a file (destination::file)
  • "file2" - writes to a second file (destination::file)
  • "rol_file" - writes to a rolling file (destination::rolling_file)
  • "rol_file2" - writes to a second rolling file (destination::rolling_file)
• If a destination is configurable, append (params) to it
  • Right now, "file", "file2", "rol_file" and "rol_file2" are configurable
    • Append (filename) to them to specify the file name. Example: "file(out.txt)" will write to the out.txt file

Examples:

• "file(out.txt) cout" - will write to a file called out.txt and to cout
• "cout debug" - will write to cout and debug window (see above)
• "cout file(out.txt) file2(dbg.txt)" - will write to cout, and to 2 files - out.txt and dbg.txt
• "cout rol_file(r.txt)" - will write to cout and to a rolling_file called r.txt

Note:

If you want to output to 2 files, don't use "file(one.txt) file(two.txt)". This will just configure "file" twice, ending up with writing only to "two.txt" file. Use "file(one.txt) file2(two.txt)" instead!

At this time, named_write does not support tags. However, it's a high priority on my TODO list, so it'll be here soon!

Parameters:

format_write_

the underlying format writer

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Member Function Documentation

template<class format_write_>

void boost::logging::writer::named_write< format_write_ >::format

(

const string_type &

format_str

)

[inline]

sets the format string: what should be before, and what after the original message, separated by "|"

Example:
"[%idx%] |\n" - this writes "[%idx%] " before the message, and "\n" after the message

If "|" is not present, the whole message is prepended to the message

template<class format_write_>

template<class destination>

void boost::logging::writer::named_write< format_write_ >::replace_destination	(	const string_type &	name,
		destination	d
	)			[inline]

Replaces a destination from the named destination.

You can use this, for instance, when you want to share a destination between multiple named writers.

template<class format_write_>

template<class formatter>

void boost::logging::writer::named_write< format_write_ >::replace_formatter	(	const string_type &	name,
		formatter	d
	)			[inline]

Replaces a formatter from the named formatter.

You can use this, for instance, when you want to share a formatter between multiple named writers.

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The documentation for this struct was generated from the following file:

• writer/named_write.hpp

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Copyright John Torjo © 2007
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