Developer's Note

Temp

Tue, 04 May 2010 10:15:29 +0900

UART

비동기식 직렬통신 방식
ex) RS-232C : 1969년 미국 EIA가 CCITT권고한 시리얼 인터페이스 규격

LPT/ECP(Extended Capabilities Port)

보통 프린트 접속을 위한 인터페이스
이후 Intel/Microsoft 에서 DMA 방식을 이용해 전송속도를 향상시킨 EPP(Enhanced Parallel Prot) ECP(Extended Capabilities Prot) 방식을 제안

USB

특징
- 조작이 간단
- 광범위한 애플리케이션 대응
- isochronous 전송의 밴드 폭을 보증
- 유연성이 높다.
- PC와의 친화성
- 저가격 충족
END POINT
- 디바이스의 일부
- 소프트웨어는 End Point를 통해서 USB device와 커뮤니케이션하며, 데이터는 End Point 로 종단함
- Descriptor중에 기술됨
- Bus Access 주파수, Latency, 밴드 폭, End Point 번호, 패킷의 최대크기
1조의 twisted piar 선 + 2개의 전원선

ISA( Industrial Standard Architecture)

사용할 수 있는 공간은 64KB (0xD0000 ~ 0xDFFFF) 이다.
메모리 영역과 I/O영역을 모두 지원
- /SMEMR, /SMEMW는 메모리 영역
- /IOR, /IOW는 I/O 영역을 위해 사용
AEN( Address Enable )
- DMA가 어드레스 신호를 생성하면 H, CPU가 생성하면 L
/IOR
- In 명령어로 I/O 장치를 읽으려고 할때 L
/IOW
- OUT명령어를 사용해 I/O장치에 데이터를 쓰려고 할때 L
Address
- I/O 영역이 64KB이므로, A[0,15]만을 사용함
메모리 영역 제어신호
- /SMEMR : 메모리 공간에서 데이터를 읽을 때 L
- /SMEMW : 메모리 공간에 데이터를 쓸 때 L
- Address : ISA버스에서는 1MB 공간에 액세스할 수 있음 A[0,19]
- Data

MCA(Micro Channel Architecture bus)

1987년 IBM
bus mastering PnP 기능 구현
높은 가격과 폐쇄적인 정책으로 실패

EISA(Extended ISA)

1988년 The Gang of Nine
bus mastering과 PnP 지원
구조가 복잡하고 높은 공급가격으로 대중화 실패

VESA(Video Electronics, Standard Association) Local bus

1992년에 발표해 대중화에 성공한 32bit bus
33MHz
bus mastering을 제대로 지원하지 못해 여러 장치가 VESA에 접근할 경우 병목 현상있음

PCI (Peripheral Component nterconnect)

현재 개인용 피씨에서 가장 많이 쓰임
32/64bit 33MHz의 성능
PnP 지원

PCMCIA ( Personal Computer Memory Card International Association)

랩탑과 PDA같은 휴대용 제품을 위한 것
다양한 장치 지원이 가능하며 소형이고 PnP 지원이 됨

CF( Compact Flash)

PCMCIA 카드가 부담되는 장치를 위한 더욱 작은 지원 장치
처음에는 PCMCIA와 마찬가지로 플래시 저장장치를지원하기 위한 것이었으나, 후에 하드디스크 및 다양한 I/O 장치들을 지원

밑단에서 네트워크 메시지를 처리해서 해당 메시지가 생성되면 callback으로 자동으로 호출해준다.

키워드 검색으로 SetDeviceCallback

XML 메시지를 보는 것은 CreateContainer를 확인해보라

I want to talk about book and arts today.

I have an unique hobby collecting books. But I don't collect every books.

As you know, A book consist of many elements, characters, paper, author's idea, picture, ink and so on.

What do you think which element is most important?

Maybe most people say contents is.

But I don't care of the content of book. when I buy a book.

The only one reason why I buy is the design of the book.

My major included some art subjects.

So I got a chance to attend typography class.

After that, I used to focus layout and character shape more than the content, when I read a book.

I know that some of students in this class can understand what is typography and the others can not.

So I prepare an example. Here is a book.

This book shows you what each typeface look like, and advices you a way how you can design content with various character sets.

We don't usually realize how important basic elements to construct an Object.

I think typeface and layout design are such a thing.

The typeface for Latin based character like Alphabet has been developing and improving continuely.

But Korean character Hangul has not.

Because We don't have the least interest in Hangul.

Many people still use typeface Gulim, when they type a report.

By the way, do you know typeface Gulim is developed by Japanese? What a shame!

We have a great character system, But many people don't realize the beauty of our character.

Let's have more interest in Hangul and its design.

Then We can make our culture more beautiful.

Thank you.

Webkit packpage update information

cairo

1.8.10

General Bug fixes
=================

* Fix path construction for the case of cairo_curve_to immediately after cairo_new_sub_path followed at some point by cairo_close_path. (Previously, the final point for the close_path was computed incorrectly.)
* Fix for cairo_push_group or cairo_pop_group with a non-empty current path. (Previously the path may have been erroneously translated when  either of these functions was called.)

* Fix to correctly report an error if cairo_surface_set_fallback_resolution is called with a value of 0 (in either axis). Previously, an assertion would occur later rather  than an error being properly reported when the original, invalid value was passed.
    Bug 23067: Using clear drawing operator crashes printing

    http://bugs.freedesktop.org/show_bug.cgi?id=23067

* Fix to handle a cairo_arc of radius 0 as equivalent to a cairo_line_to to the center coordinate, (previously cairo would do nothing for a cairo_arc call with a radius of 0).

Backend-specific bug fixes

==========================

cairo-xlib

----------

* Fix to correctly copy from a Window source. Previously, cairo was failing to include the contents of any sub-windows when copying from a Window source.

    Bug 12996: Xlib source surface fast-paths do not use

    IncludeInferiors, while slow paths do
    https://bugs.freedesktop.org/show_bug.cgi?id=12996

cairo-ft

--------

* Fix conversion of freetype index to UCS4 value, (which would previously miss the first character and cause the space glyph to map  to 0x00A0 instead of 0x0020).

cairo-pdf

---------

* Fix Type 1 subsetting to avoid generating corrupt data.

    Launchpad Ubuntu/cups bug 419143: Printing from evince (and

    perhaps other GTK apps) to PostScript printers is broken

    https://bugs.launchpad.net/ubuntu/+source/cups/+bug/419143

* Fix Type 1 subsetting to correctly identify binary eexec data.

* Fix Type 1 subsetting to include fixed-content portion in the embedded font, (since some fonts may contain additional PostScript  code after the cleartomark).

* Fix Type 1 subsetting to append "cleartomark" operator for binary fonts that don't include it.

Build fixes

===========

* Fix to compile on OpenBSD, (which has a libpng.pc file but none of libpng10.pc, libpng12.pc, or libpng13.pc which cairo was looking for previously).

expat

2.0.1

Release 2.0.1 of the Expat XML parser is a bugfix release resolving both code and build related issues. Changes include:

Fixed: The character data handler's calling of XML_StopParser() was not handled properly; if the parser was stopped and the handler set to NULL, the parser would segfault.
Fixed: Expat failed on EBCDIC systems as it assumed some character constants to be ASCII encoded.
Minor cleanups of the test harness.
Minor fixes for xmlwf and example programs.
Fixes and improvements for the Windows platform. New Windows directory structure.
Build fixes for various platforms: HP-UX, Tru64, Solaris 9.
Build fixes for Unix:
- Refreshed config.sub/config.guess.
- Support both, DESTDIR and INSTALL_ROOT, without relying on GNU-Make specific features.
- Patched configure.in to work better with Intel compiler.
- Fixes to Makefile.in to have make check work correctly.
Added Open Watcom support.

GTK+

2.18

GTK+ 2.18 adds new functionality while maintaining source and binary compatibility with GTK+ 2.16. Highlights of new features and improvements in GTK+ 2.18 are:

GtkInfoBar
A new widget to show a transient ‘message area’ inside a content pane. The API is similar to GtkDialog and supports theming for different message types (warnings, errors, etc)

GtkBuilder

Scale marks can be specified in builder markup
GtkAssistant action widgets can be added in builder markup

GtkLabel
GtkLabel can show embedded URLs, much like SexyUrlLabe

GtkEntry
GtkEntry has been refactored to follow the model-view pattern, with GtkEntryBuffer as model. One intended use case for this is to support ’secure memory’ for password entries

File chooser

Backup files are hidden by default
GTK+ remembers the sorting state of the file list
File sizes are shown by default
The ‘Create Folder’ button can be disabled with the the ::create-folders property

Printing support

GTK+ supports authentication against CUPS servers
A backend for the PAPI printing system has been added
The file and lpr backends can print multiple pages per sheet
The file backend can produce svg files
GTK+ supports printing an application-defined ’selection’ in addition to the usual page ranges
The print dialog can optinally include the page setup controls, avoiding the need for a separate page setup dialog in many situations

Theming support

The bullet character used in invisible entries can be set by themes with the ::invisible-char style property
The file chooser can show different icons for xdg user dirs. The icon names are folder-documents, folder-download, folder-music, folder-pictures, folder-publicshare, folder-templates and folder-video
The GtkInfoBar uses symbolic colors for theming its background color depending on the message type. The color names are info_fg_color, info_bg_color, warning_fg_color”, warning_bg_color, etc.

GDK changes
GDK has been rewritten to use ‘client-side windows’. This means that GDK maintains its own window hierarchy and only uses X windows where it is necessary or explicitly requested. Some of the benefits of this change are

Reduced flicker
The ability to do transformed and animated rendering of widgets
Easier embedding of GTK+ widgets, e.g. into Clutter scene graphs
See gdk-demo for some simple examples of client-side windows in action. See the documentation for information about possible problems when moving to client-side windows.

GLib

2.22

GLib 2.22 is a stable release adding an incremental improvement in functionality over GLib 2.20 while maintaining binary and source compatibility.

Major new features include:

GArray, GPtrArray, GByteArray, GTree and GMappedFile can be reference counted.
GLib can be forced to reload the XDG user directory mapping.
The GLib mainloop supports per-thread default contexts.
GIO now provides types and methods for IP addresses and UNIX domain socket addresses.
GResolver provides asynchronous and cancellable APIs for resolving hostnames, reverse lookup of IP addresses and resolving SRV records.
Support for network IO has been added to GIO, including low-level socket API and high-level API for network connections and services.
GIOStream and its subclasses have gained support for read-write access.
GIO supports starting and stopping of drives, which can be used in connection with external hard disk enclosures, disk arrays, iSCSI devices, etc.
GIO supports user interaction during unmount and eject operations.
GIO can store and retrieve per-file metadata.

XORG-SERVER

1.8

New input hotplug and configuration system, including:

HAL Replacement - udev support for Linux integrated, other OS'es TBD
xorg.conf.d

The X.org X server 1.8.0 is now available. It's pretty close to RC2, with some XQuartz and Cygwin/X changes, and some various input cleanups.

One other notable change since RC3 is that udev is now the default input device autoconfiguration mechanism where available, and the server installs a 10-evdev.conf file to make sure you get input devices after installing the new server.



Dan Nicholson (1):

      config/udev: Prefer product name from attribute rather than uevent



Fernando Carrijo (1):

      Cleanup some comments in SpriteRec



Jeremy Huddleston (13):

      Revert "XQuartz: Explicitly pass a bellProc to make XBell() work again."

      XQuartz: GLX: Fix Availability for Tiger ppc workaround

      XQuartz: Minor cleanup

      XQuartz: xpbproxy: Cleanup xpbproxy threading

      XQuartz: pbproxy: Make standalone xpbproxy respect the launchd prefix

      XQuartz: Constrain the pointer to the updated display bounds on display reconfigure.

      XKB: Fix garbage initialization

      XQuartz: Workaround weird key data reported on some layouts

      GLX: Remove a redundant initialization

      darwin: Generate crash reports on FatalError()

      XQuartz: Re-query dixScreenOrigins as the value could've changed.

      darwin: Correct inline assembly for  ___crashreporter_info__

      Bump bundle version to 2.5.1



Keith Packard (2):

      Install 10-evdev.conf in $(prefix)/etc/X11/xorg.conf.d under udev

      xserver 1.8.0



Michel Dänzer (1):

      Xext: Fix cursor reference counting hazard.



Mikhail Gusarov (1):

      kdrive: Bump evdev maxKeycode



Peter Harris (1):

      Fix crash when all glyphs of a given depth are freed, but not all glyphsets



Peter Hutterer (4):

      configure: Always define XINPUT.

      xfree86: remove if 1 from the dawn of time.

      xfree86: merge driver from the input class into the options.

      configure: enable udev backend as "auto"



Rami Ylimaki (1):

      os: Prevent backtrace from being stopped in noreturn functions.



Ruediger Oertel (2):

      xfree86: Handle driver autoconfiguration when .conf files exist

      Remove now obsolete function chooseVideoDriver



Tiago Vignatti (1):

      xfree86: die gracefully in the vga arbiter if AddScreen fails



Tomas Carnecky (1):

      Fix typos in the swap functions



Yaakov Selkowitz (14):

      Cygwin/X: Fix make dist after 11252ed82e1f361b99e86521ac9314f868bd1a3a

      Cygwin/X: Fix windres rule for automake silent rules

      Rename xdmx client to dmxinfo

      Use libtool -export-dynamic flag for portability

      kdrive: Use $(MAKE) in relink rules

      Use EXEEXT in relink rules for portable DDXs

      Fix relink targets for silent rules

      Respect value of SED from configure

      Fix .man.N targets for AM_SILENT_RULES

      Catch errors in recursive relink targets

      mi: remove deprecated #include <X11/extensions/xf86bigfstr.h> in miinitext.c

      Xext: fix old-style function definitions in xf86bigfont.c

      New header for XF86Bigfont server functions

      Cygwin/X: Make X -> XWin symlink during install

1.7

X Input 2.0
Mandatory XKB
Support for symbol visibility
EXA mixed pixmaps
VGA arbitration

zlib

1.2.5

Version 1.2.5 fixes bugs in gzseek() and gzeof() that were present in version 1.2.4 (March 2010). All users are encouraged to upgrade immediately.

1.2.4

Version 1.2.4 has many changes over 1.2.3, including these improvements:

Fixed bugs in adler32_combine(), compressBound(), and deflateBound()
Wholesale replacement of gz* functions with faster versions
As part of that, added gzbuffer(), gzoffset(), gzclose_r(), and gzclose_w() functions
Faster Z_HUFFMAN_ONLY and Z_RLE compression for images and other specialized compression
Added flush options Z_BLOCK to deflate() and Z_TREES to inflate() for finer control
Added inflateReset2() and inflateMark() functions, the latter to aid in random access applications
Added LFS (Large File Summit) support for 64-bit file offsets and many other portability improvements
Updated examples in examples/ and updated third-party contributions in contrib/

freetype

2.3.12

CHANGES BETWEEN 2.3.11 and 2.3.12

  I. IMPORTANT CHANGES

    - For  `FT_Open_Face',  new  parameters  are  available  to ignore

      preferred family names: FT_PARAM_TAG_IGNORE_PREFERRED_FAMILY and

      FT_PARAM_TAG_IGNORE_PREFERRED_SUBFAMILY.

  II. MISCELLANEOUS

    - Support  for  incremental  font  loading  (controlled  with  the

      FT_CONFIG_OPTION_INCREMENTAL macro) is now active by default.

    - Better support for vertical metrics.

    - Various minor bug fixes.

more information : http://freetype.sourceforge.net/index2.html#release-freetype-2.3.12

libxml2

2.7.7

Improvements: Adding a --xpath option to xmllint (Daniel Veillard), Make HTML parser non-recursive (Eugene Pimenov)
Portability: relaxng.c: cast to allow compilation with sun studio 11 (Ben Walton), Fix build failure on Sparc solaris (Roumen Petrov), use autoreconf in autogen.sh (Daniel Veillard), Fix build with mingw (Roumen Petrov), Upgrade some of the configure and autogen (Daniel Veillard), Fix relaxNG tests in runtest for Windows runtest.c: initialize ret (Rob Richards), Fix a const warning in xmlNodeSetBase (Martin Trappel), Fix python generator to not use deprecated xmllib (Daniel Veillard), Update some automake files (Daniel Veillard), 598785 Fix nanohttp on Windows (spadix)
Bug Fixes: libxml violates the zlib interface and crashes (Mark Adler), Fix broken escape behaviour in regexp ranges (Daniel Veillard), Fix missing win32 libraries in libxml-2.0.pc (Volker Grabsch), Fix detection of python linker flags (Daniel Macks), fix build error in libxml2/python (Paul Smith), ChunkParser: Incorrect decoding of small xml files (Raul Hudea), htmlCheckEncoding doesn't update input-end after shrink (Eugene Pimenov), Fix a missing #ifdef (Daniel Veillard), Fix encoding selection for xmlParseInNodeContext (Daniel Veillard), xmlPreviousElementSibling mistake (FranÃ§ois Delyon), 608773 add a missing check in xmlGROW (Daniel Veillard), Fix xmlParseInNodeContext for HTML content (Daniel Veillard), Fix lost namespace when copying node * tree.c: reconcile namespace if not found (Rob Richards), Fix some missing commas in HTML element lists (Eugene Pimenov), Correct variable type to unsigned (Nikolay Sivov), Recognize ID attribute in HTML without DOCTYPE (Daniel Veillard), Fix memory leak in xmlXPathEvalExpression() (Martin), Fix an init bug in global.c (Kai Henning), Fix xmlNodeSetBase() comment (Daniel Veillard), Fix broken escape behaviour in regexp ranges (Daniel Veillard), Don't give default HTML boolean attribute values in parser (Daniel Veillard), xmlCtxtResetLastError should reset ctxt-errNo (Daniel Veillard)
Cleanups: Cleanup a couple of weirdness in HTML parser (Eugene Pimenov)

SQLITE3

3.6.23.1

SQLite version 3.6.23.1 is a patch release to fix a bug in the offsets() function of FTS3 at the request of the Mozilla.

3.6.23

SQLite version 3.6.23 is a regular bimonthly release of SQLite. Upgrading from the prior release is purely optional.

This release contains new pragmas: the secure_delete pragma, and the compile_options pragma. There are a new SQL functions: sqlite_compileoption_used() and sqlite_compileoption_get(). New C/C++ interfaces: sqlite3_compileoption_used(), sqlite3_compileoption_get(), SQLITE_CONFIG_LOG, and sqlite3_log().

This release also includes several minor bug fixes and performance improvements. Support for SQLITE_OMIT_FLOATING_POINT is enhanced. There are on-going improvements to FTS3.

The ".genfkey" command in the Command Line Interface has been removed. SQLite has supported standard SQL foreign key constraints since version 3.6.19 and so the ".genfkey" command was seen as an anachronism.

more information : http://www.sqlite.org/news.html

libpng

1.4.1

Changes to Libpng from version 1.2.43 to 1.4.1 (February 25, 2010)

Libpng-1.4.1 was released by the PNG Development Group on February 25, 2010.  Important new features include support for the iTXt chunk and a function for limiting the amount of memory that a possibly malicious compressed chunk can consume.  

Some long-deprecated functions and features have been removed.  A new private header file that is not visible to applications has been created, to improve our ability to maintain binary compatibility among future libpng versions.

Specifically,

1. Private libpng prototypes and macro definitions were moved from png.h and pngconf.h into a new pngpriv.h header file that is notvisible to applications.

2. Some obsolete/deprecated macros and functions have been removed.

   a. We eliminated the obsolete, unused pnggccrd.c and pngvcrd.c files

      and related makefiles.

   b. We removed the typecasted NULL definitions such as

          #define png_voidp_NULL    (png_voidp)NULL

      If you used these in your application, just use NULL instead.

   c. We eliminated the PNG_1_0_X and PNG_1_2_X macros.

   d. We eliminated the PNG_LEGACY_SUPPORTED macro.

   e. We removed many WIN32_WCE #ifdefs.

   f. We removed the functions png_read_init(info_ptr),

      png_write_init(info_ptr), png_info_init(info_ptr),

      png_read_destroy(), and png_write_destroy().

      They have been deprecated since libpng-0.95.

   g. We removed the png_permit_empty_plte() function. It has been

      deprecated since libpng-1.0.9.  Use png_permit_mng_features() instead.

   h. We removed the obsolete stub functions png_get_mmx_flagmask(),

      png_set_mmx_thresholds(), png_get_asm_flags(),

      png_get_mmx_bitdepth_threshold(), png_get_mmx_rowbytes_threshold(),

      png_set_asm_flags(), and png_mmx_supported()

   i. We removed the obsolete png_check_sig(), png_memcpy_check(), and

      png_memset_check() functions.  Instead use !png_sig_cmp(),

      png_memcpy(), and png_memset(), respectively, i.e.,



      replace

        png_check_sig(buf, 8)

      with

        png_sig_cmp(buf, 0, 8) == 0



      replace

        png_memcpy_check(png_ptr, dest, src, length)

      with

        png_memcpy(dest, src, length)



      and replace

        png_memset_check(png_ptr, dest, value, length)

      with

        png_memset(dest, value, length)



   j. We removed support for global arrays to improve thread safety.

   k. We removed support for numbered error messages by default, since we

      never got around to actually numbering the error messages. The function

      png_set_strip_error_numbers() was removed from the library by default.

   l. The png_zalloc() and png_zfree() functions are no longer exported.

      The png_zalloc() function no longer zeroes out the memory that it

      allocates.

   m. The function png_set_gray_1_2_4_to_8() was removed. It has been

      deprecated since libpng-1.0.18 and 1.2.9, when it was replaced with

      png_set_expand_gray_1_2_4_to_8() because the former function also

      expanded palette images.

3. Several function prototypes were changed.

   a. We changed the prototype for png_malloc() from

      png_malloc(png_structp png_ptr, png_uint_32 size) to

      png_malloc(png_structp png_ptr, png_alloc_size_t size)

   b. We changed the prototypes of png_get_compression_buffer_size() and

      png_set_compression_buffer_size() to work with png_size_t instead of

      png_uint_32.

4. We added some new features:

   a. We enabled iTXt chunk support by default.  This changes the png_text

      structure by adding the itxt_length, lang, and lang_key members.

   b. We added the functions png_set_benign_errors(), png_benign_error(),

      and png_chunk_benign_error().  With these, you can choose to treat

      certain normally fatal errors as nonfatal.

   c. Support for setting the maximum number of ancillary chunks that the

      application will store and the amount of memory that the application

      will allocate for reading chunks was added, as a security measure.

      The functions png_set_chunk_cache_max(), png_get_chunk_cache_max()

      png_set_chunk_malloc_max(), and png_get_chunk_malloc_max()

      were added to the library. Also, in libpng-1.4.1, support was

      added for setting default limits via macros PNG_USER_CHUNK_CACHE_MAX

      and PNG_USER_CHUNK_MALLOC_MAX. These are set to 0, meaning unlimited,

      in the libpng distribution.

   d. We added the png_calloc() function and used it in place of

      of "png_malloc(); png_memset();" except in the case in png_read_png()

      where the array consists of pointers; in this case a "for" loop is used

      after the png_malloc() to set the pointers to NULL, to give robust.

      behavior in case the application runs out of memory part-way through

      the process.

   e. We implemented support for I/O states by adding png_ptr member io_state

      and functions png_get_io_chunk_name() and png_get_io_state() in pngget.c

   f. We added PNG_TRANSFORM_GRAY_TO_RGB to the available high-level

      input transforms.

5. Other changes

   a. We changed the names of the png_struct and info_struct members "trans"

      and "trans_values" to "trans_alpha" and "trans_color", respectively.

   b. Checking for and reporting of errors in the IHDR chunk is more thorough.

   c. We removed the trailing '.' from the warning and error messages.

   d. Direct access to png_ptr->jmpbuf has been deprecated since libpng

      version 1.0.6, and libpng now generates a warning about it.

      To avoid such warnings, change

        setjmp(png_ptr->jmpbuf)

      to

        setjmp(png_jmpbuf(png_ptr))

   e. In libpng-1.4.1, and backported to libpng-1.2.43 and 1.0.53, the

      png_decompress_chunk() function is much more efficient in terms of

      CPU time and memory allocated.

6. Building and linking with the libraries

    The configure script and most of the makefiles will build

    libpng10   (libpng-1.0.52, provided for legacy 1.0.x applications)

    libpng12   (libpng-1.2.42, stable version, for recent legacy 1.2.x apps)

    libpng14   (libpng-1.4.0, the current version)

    libpng     (whichever of the above was built last!)

    You should build them in order

       1) libpng10 (if you must; you probably don't need libpng10)

       2) libpng12 (overwrites the libpng created in step 1)

       3) libpng14 (overwrites the libpng created in step 2)



    Optionally, if you aren't ready to switch, you can build them

    in order

       1) libpng14

       2) libpng12 (this will overwrite the libpng created in step 1)

    If you simply want to link with the last version built, use

    -lpng -lz when building your application.  If you need a specific

    version, use, e.g., -lpng12 -lz.  Most applications can probably

    simply use -lpng -lz.

Send comments to png-mng-implement at lists.sf.net (subscription required;

visit https://lists.sourceforge.net/lists/listinfo/png-mng-implement.net

to subscribe) or to glennrp at users.sourceforge.

ICU

4.0.1

ICU4C 4.0.1 is a maintenance release of ICU4C 4.0. The primary changes of this release were:

Updated time zone data to 2008i
Technical preview of string search implementation using Boyer-Moore algorithm (#6286). For detail information, please see the tech note here.
#5691 Conversion: consistent illegal sequences
#6435 Bad @stable ICU4.0 tags
#6597 TestDisplayNamesMeta failure
#6670 Test failure in format/TimeZoneTest/TestShortZoneIDs

4.0

ICU is the premier library for software internationalization. ICU 4.0 is a major reference release of ICU, with new features, new APIs, and many bug fixes in data and code.

Major changes in ICU 4.0 include the following:

Common Changes
- Unicode 5.1 (#5696)
- Locale Data: ICU uses and supports data from Common Locale Data Repository (CLDR) 1.6 , which includes many improvements in quality and quantity of data.
- add/removeLikelySubtags (#6124)
- Charset converter file size improvement (#5987)
- Date Interval Formatting (#6157) Note: Calendar type supported by this feature is Gregorian only in this release.
- Improved Plural support
ICU4C Specific Changes
Additional Calendars
- Chinese (#4081)
- Coptic/Ethiopic (#4571)
ICU4J Specific Changes
- Charset
  - Graduated from Technology Preview status
  - ICU2022 Converter (#5791)
  - HZ Converter (#6128)
  - SCSU/BOCU-1 Converter (#2147)
  - Charset Converter Callback (#6144)
- Thai Dictionary break iterator (#5385)
- JDK TimeZone support (#5975)
- Locale Service Provider (#5976)
- More convenient formatting of year+month, day+month, and other combinations (#6304)
- Simple Duration Formatting (#6303)
ICU4C Security Fixes
ICU4C 4.0 resolves the vulnerabilities CVE-2007-4770 and CVE-2007-4771 which were found in earlier versions of ICU. The standard ICU tests verify that these have been corrected, however, the updated versions of the previous tests may be run by applying the following patch to ICU 4.0: r24324. As well, ICU4C and ICU4J 4.0 resolve the issue underlying CVE-2008-1036.

libsoup

2.30.0

Changes in libsoup from 2.29.91 to 2.30.0:

     * Fixed a crash in the whitespace-stripping code in

          soup_uri_new() [#612644, "arnaud.lb"]

  * Update content-sniffing algorithm to match Chrome and the

          soon-to-be-updated sniffing spec. [#611502, Gustavo Noronha

          Silva]

      * We now handle "Content-Encoding: x-gzip" as well as "gzip"

        (even though "x-gzip" has been deprecated for more than 10

        years). [#611476]

       * Fixed leaks found by valgrind

   * Make the "make check" programs only bind to 127.0.0.1, not

          any public network interfaces. [#609489, Saleem Absulrasool]

  * Add a test to sniffing-test to make sure that Content-Type

          parameters are preserved correctly. [Gustavo Noronha Silva]

more information : http://git.gnome.org/browse/libsoup/tree/NEWS

pango

1.28.0

Overview of changes between 1.27.1 and 1.28.0

=============================================

- [HB] Fix leak when duplicating blob

- Misc bug fixes

- Bugs fixed:

    Bug 611033 - Layout using ATSUI fontmap treats absolute font sizes a...

    Bug 605655 - Pango 1.26.2 introduces kerning bug

    Bug 611229 - Pango reads from uninitialized memory

    Bug 594101 - [Indic] needed character class data updates to support unicode 5.1

    Bug 345066 - backspace changes independent indic characters

    Bug 609326 - Complex script shaping failed in the FT2 backend on Windows

    Bug 604128 - Applications crash when displaying Hebrew characters

    Bug 608923 - Incorrect/broken ligatures on MacOS

    Bug 610791 - checks fail for unused documented symbols

As already mentioned, a significant capability difference between
cairo and OpenVG is the fact that cairo provides multiple backends,
aiming to unify display and print output. Another is that OpenVG
provides no direct support for fonts or text, which are often the
dominant element of 2D user interfaces.

I would expect this to be the more natural thing to do. Conceptually VG sits
at the same level as GL in the stack, and both VG and GLES use the EGL API
for context and window management. You could implement EGL over cairo but
it'd be awkward.

A quick skim through the header files shows that there is no support (not even XRender style) for text or fonts. It also lacks some of the compositing operations, but that is probably of little importance. Otherwise it looks very close to Cairo.
Conversely OpenVG does have support for perspective transforms of images, an important graphics function that is missing from Cairo.

http://en.wikipedia.org/wiki/Cairo_(graphics)#cite_note-5

GTK+, starting in 2005 with version 2.8, uses cairo to render the majority of its widgets[10].

The WebKit framework uses cairo for all rendering in the GTK+ port. Support has also been added for SVG and <canvas> content using cairo.

1: http://www.khronos.org/openvg/
2: http://www.openedhand.com/
3: http://ivanleben.blogspot.com/2007/07/shivavg-open-source-ansi-c-openvg.html
4: http://www.amanithvg.com/
5: http://gitweb.freedesktop.org/?p=users/pippin/cairo.git;a=blob;f=src/cairo-openvg-surface.c;hb=openvg
6: http://people.freedesktop.org/~pippin/cairo/OpenVG/cairovgtest.tar.gz

fbdev is an Xorg driver for framebuffer devices. This is a non-accelerated driver, the following framebuffer depths are supported: 8, 15, 16, 24. All visual types are supported for depth 8, and TrueColor visual is supported for the other depths. Multi-head configurations are supported.

openVG spec 문서

It is possible to provide OpenVG on a platform without supporting EGL. In this case, the host operating system must provide some alternative means of creating a context and binding it to a drawing surface and a rendering thread.

Most OpenVG implementations are expected to make use of version 1.2 or later of the EGL API to obtain drawing contexts. This section provides only a partial, non-normative description of some aspects of the use of EGL that are specific to OpenVG. Refer to the EGL 1.2 specification for more details.

EGL can be implemented on multiple operating systems (such as Symbian, embedded Linux, Unix, and Windows) and native window systems (such as X and Microsoft Windows). Implementations may also choose to allow rendering into specific types of EGL surfaces via other supported native rendering APIs, such as Xlib or GDI. EGL provides:
Mechanisms for creating rendering surfaces (windows, pbuffers, pixmaps) onto which client APIs can draw and share
Methods to create and manage graphics contexts for client APIs
Ways to synchronize drawing by client APIs as well as native platform rendering APIs.

EGL provides mechanisms for creating rendering surfaces onto which client APIs can draw, creating graphics contexts for client APIs , and synchronizing drawing by client APIs as well as native platform rendering APIs. EGL does not explicitly support remote or indirect rendering, unlike the similar GLX API.

2.2.3 Interaction With Native Rendering
Native rendering will always be supported by pixmap surfaces (to the extent that native rendering APIs can draw to native pixmaps). Pixmap surfaces are typically used when mixing native and client API rendering is desirable, since there is no need to move data between the back buffer visible to the client APIs and the native pixmap visible to native rendering APIs. However, pixmap surfaces may, for the same reason, have restricted capabilities and performance relative to window and pbuffer surfaces.

Native rendering will not be supported by pbuffer surfaces, since the color buffers of pbuffers are allocated internally by EGL and are not accessible through any other means.
Native rendering may be supported by window surfaces, but only if the native window system has a compatible rendering model allowing it to share the back color buffer, or if single buffered rendering to the window surface is being done.
When both native rendering APIs and client APIs are drawing into the same underlying surface, no guarantees are placed on the relative order of completion of operations in the different rendering streams other than those provided by the synchronization primitives discussed in section 3.8.
Some state is shared between client APIs and the underlying native window system and rendering APIs, including color buffer values in window and pixmap surfaces.

2.3 Direct Rendering and Address Spaces
EGL is assumed to support only direct rendering, unlike similar APIs such as GLX. EGL objects and related context state cannot be used outside of the address space in which they are created. In a single-threaded environment, each process has its own address space. In a multi-threaded environment, all threads may share the same virtual address space; however, this capability is not required, and imple- mentations may choose to restrict their address space to be per-thread even in an environment supporting multiple application threads.
Context state, including both the client and server state of OpenGL ES contexts, exists in the client’s address space; this state cannot be shared by a client in another process.
Support of indirect rendering (in those environments where this concept makes sense) may have the effect of relaxing these limits on sharing. However, such support is beyond the scope of this document.

xgl

Backends
OpenGL does not specify how to initialize a display and manipulate drawing contexts. Instead these operations are handled by an API specific to the native windowing system. So far there are two different backend approaches to solving this initialization problem. Most likely the majority of each backend will contain the same code and the differences will primarily be in the initialization portions of the servers.

Mesa's Xlib driver provides an emulation of the GLX interface so that OpenGL programs which use the GLX API can render to any X display, even those that don't support the GLX extension. Effectively, the Xlib driver converts all OpenGL rendering into Xlib calls.

OpenGL-based programs must link with the libGL library. libGL implements the GLX interface as well as the main OpenGL API entrypoints. When using indirect rendering, libGL creates GLX protocol messages and sends them to the X server via a socket. When using direct rendering, libGL loads the appropriate 3D DRI driver then dispatches OpenGL library calls directly to that driver.

libGL also has the ability to support heterogeneous, multi-head configurations. That means one could have two or more graphics cards (of different types) in one system and libGL would allow an application program to use all of them simultaneously.

OpenGL

Fri, 30 Apr 2010 12:36:22 +0900

Primary textbook

pauline Baker and Donald Hearn. Computer Graphics

local illumination

hermit curve

버퍼를 지우는 것보다는 지우려는 색상으로 framebuffer를 채우는 것이 더 빠르다.

브래즈넘 알고리즘

Scan-line Algorithm

super sampling

색상을 결정을 주변의 색을 더해서 평균해 그 pixel의 색상을 결정한다.

Weighted Filtering

Cone Filter / Gaussian Filter

splat

Cohen-Sutherland Algorithm

clipping

line clipping : parametric algorithm

polygon clipping : weiler-atherton algorithm

glut

glutTimer function은 일정 시간 후 자기 자신을 재귀적으로 호출하도록 설정해야함

마지막 value는 counter 수치로 한번 불릴때 마다 1씩 떨어짐

사원수

짐볼락 : 회전축이 겹치면서 나타나는 연산 오류

쿼터니안은 회전 이동만 처리 가능

http://www.g-matrix.pe.kr/feature/3dengine/eulerangle.htm

http://www.g-matrix.pe.kr/feature/3dengine/quaternion.htm

http://gamedev.net/reference/articles/article1095.asp
http://www.gamasutra.com/features/19980703/quaternions_01.htm(아 이디 필요함)
http://gamedev.net/reference/articles/article1691.asp
http://freefall.freehosting.net/articles/quaternions_1.html
http://www.daimi.au.dk/~mbl/cgcourse/wiki/_files/shoemake94.pdf

viewport와 view frustum 비율을 어떻게 맞출 것인가?

glFrustum와 gluPerspective의 사용 구분

near plane을 1.0로 잡았다면 가로 세로 비에 있어서 작은 쪽이 최소 1 이상이어야한다. 그리고 그 비율대로 near plane의 ratio를 결정한다.

    GLfloat ratio = 0.0f;
    GLfloat windowScalingRatio = 0.0f;
    GLfloat w = 0.0f, h = 0.0f;
    if (width <= height) {
        w = 1.0;
        h = (GLfloat)height / (GLfloat)width;
    } else {
        w = (GLfloat)width / (GLfloat)height;
        h = 1.0f;
    }

    static GLfloat nearPlaneWidth = w, nearPlaneHeight = h;

    GLSize2f winScaleRatio = {(GLfloat)width / (GLfloat)windowSize.width,
                            (GLfloat)height / (GLfloat)windowSize.height };

    if (width <= height) {
        nearPlaneWidth = nearPlaneWidth * winScaleRatio.width;
        nearPlaneHeight = nearPlaneHeight * winScaleRatio.height;
        glFrustum(-(GLfloat)nearPlaneWidth/2.0f , (GLfloat)nearPlaneWidth/ 2.0f ,
            -(GLfloat)nearPlaneHeight/2.0f, (GLfloat)nearPlaneHeight/2.0f,
            1.0, 500.f);
    } else {
        nearPlaneWidth = nearPlaneWidth * winScaleRatio.width;
        nearPlaneHeight = nearPlaneHeight * winScaleRatio.height;
        glFrustum(-(GLfloat)nearPlaneWidth/2.0f, (GLfloat)nearPlaneWidth/2.0f ,
            -(GLfloat)nearPlaneHeight/2.0f, (GLfloat)nearPlaneHeight/2.0f,
            1.0, 500.f);
    }

K-DOP

raycasting

각 버터에 픽셀 하나당 카메라에서 출발하는 레이를 쏴서 제일 먼저 충돌하는 폴리곤을 찾아낸다.

local illumination

화면에 각 픽셀을 결정하기 위해서 카메라에서 해당 window pixel로 ray를 쏴서 어느 폴리곤의 primitive가 화면에 보여지는 지 찾고 다시 그 픽셀에서 광원쪽으로의 빛을 고려해서 색상을 결정한다.

석고 표면은 난반사가 잘일어나서 뽀송뽀송하다.

gouraud shading은 색상값의 보간

pong shading은 노말값의 보간

오픈지엘은 gouraud shading이 기본이다.

B-SPLINE

NURBS

텍스쳐 매핑 좌표는 버텍스에서 텍스쳐의 uv 좌표계로 점을 역으로 계산한다.

mipmap은 여러개 크기의 텍스쳐를 미리 만들어 놓는것이다.

minification : 텍스쳐의 여러개 색상이 하나의 픽셀에 표현될 때

magnification : 하나의 텍스쳐 색상이 여러개의 pixel에 표현이 될때

HDR(High dynamic range rendering)

Summed Area Tables

Reflection mapping

블랜딩

RGBA 에서 alpha 값을 불투명도를 삼아서 두 색상의 곱에 대한 기여도로 사용한다.

git

Tue, 12 Jan 2010 12:50:21 +0900

새 repositry 만들기

source의 root가 될 directory로 이동을 한 git init을 실행하면된다.

cd $SRC_ROOT

git init

General

Tue, 12 Jan 2010 11:13:02 +0900

.bashrc reference

사용자 계정의 home directory에 .bashrc 파일이 존재하면 이를 참고해서 사용자 계정의 환경 설정을 한다.

Ubuntu linux의 default .bashrc는 아래와 같다

# ~/.bashrc: executed by bash(1) for non-login shells.
# see /usr/share/doc/bash/examples/startup-files (in the package bash-doc)
# for examples

# If not running interactively, don't do anything
[ -z "$PS1" ] && return

# don't put duplicate lines in the history. See bash(1) for more options
export HISTCONTROL=ignoredups
# ... and ignore same sucessive entries.
export HISTCONTROL=ignoreboth

# check the window size after each command and, if necessary,
# update the values of LINES and COLUMNS.
shopt -s checkwinsize

# make less more friendly for non-text input files, see lesspipe(1)
[ -x /usr/bin/lesspipe ] && eval "$(SHELL=/bin/sh lesspipe)"

# set variable identifying the chroot you work in (used in the prompt below)
if [ -z "$debian_chroot" ] && [ -r /etc/debian_chroot ]; then
    debian_chroot=$(cat /etc/debian_chroot)
fi

# set a fancy prompt (non-color, unless we know we "want" color)
case "$TERM" in
    xterm-color) color_prompt=yes;;
esac

# uncomment for a colored prompt, if the terminal has the capability; turned
# off by default to not distract the user: the focus in a terminal window
# should be on the output of commands, not on the prompt
#force_color_prompt=yes

if [ -n "$force_color_prompt" ]; then
    if [ -x /usr/bin/tput ] && tput setaf 1 >&/dev/null; then
    # We have color support; assume it's compliant with Ecma-48
    # (ISO/IEC-6429). (Lack of such support is extremely rare, and such
    # a case would tend to support setf rather than setaf.)
    color_prompt=yes
    else
    color_prompt=
    fi
fi

if [ "$color_prompt" = yes ]; then
    PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
else
    PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
fi
unset color_prompt force_color_prompt

# If this is an xterm set the title to user@host:dir
case "$TERM" in
xterm*|rxvt*)
    PROMPT_COMMAND='echo -ne "\033]0;${USER}@${HOSTNAME}: ${PWD/$HOME/~}\007"'
    ;;
*)
    ;;
esac

# Alias definitions.
# You may want to put all your additions into a separate file like
# ~/.bash_aliases, instead of adding them here directly.
# See /usr/share/doc/bash-doc/examples in the bash-doc package.

#if [ -f ~/.bash_aliases ]; then
#    . ~/.bash_aliases
#fi

# enable color support of ls and also add handy aliases
if [ "$TERM" != "dumb" ] && [ -x /usr/bin/dircolors ]; then
    eval "`dircolors -b`"
    alias ls='ls --color=auto'
    #alias dir='ls --color=auto --format=vertical'
    #alias vdir='ls --color=auto --format=long'

    #alias grep='grep --color=auto'
    #alias fgrep='fgrep --color=auto'
    #alias egrep='egrep --color=auto'
fi

# some more ls aliases
alias ll='ls -l'
alias la='ls -A'
alias l='ls -CF'

# enable programmable completion features (you don't need to enable
# this, if it's already enabled in /etc/bash.bashrc and /etc/profile
# sources /etc/bash.bashrc).
if [ -f /etc/bash_completion ]; then
    . /etc/bash_completion
fi

Unix/Linux에 대한 일반적인 사항

명령 프롬프트의 구성

[계정명@서버명 폴더명]$ or [계정명@서버명 폴더명]#

이때 $은 사용자 계정을 사용 중임을 뜻하고 #은 루트계정을 사용 중임을 뜻한다.

Root 권한으로 변경

su 명령 후 password 입력

admin 그룹에 추가

/etc/group 파일을 아래와같이 추가한다

admin:x:115:user,addUser

user는 기존에 추가되어있는 user이고 addUser는 새로 admin 그룹에 추가하려는 사용자명이다

IP 설정법

ifdown eth0 (랜카드 사용을 중지한다.)
/etc/network/interfaces (ip설정이 있는 곳으로 이동)
vi interfaces ( interfaces 설정 파일을 vi 에디터로 수정한다. )
- auto lo
- iface lo inet loopback
- auto eth0
- iface eth0 inet static
- address xxx.xxx.xxx.xxx
- netmask xxx.xxx.xxx.xxx
- network xxx.xxx.xxx.xxx
- broadcast xxx.xxx.xxx.xxx
- dns-nameservers xxx.xxx.xxx.xxx

Samba를 이용한 공유폴더 지정 GUI 프로그램 설치

프로그램 > 추가/제거 를 누르고 찾기 창에 'samba' 를 검색한다

Samba config file sample

# Sample configuration file for the Samba suite for Debian GNU/Linux.
#
#
# This is the main Samba configuration file. You should read the
# smb.conf(5) manual page in order to understand the options listed
# here. Samba has a huge number of configurable options most of which
# are not shown in this example
#
# Any line which starts with a ; (semi-colon) or a # (hash)
# is a comment and is ignored. In this example we will use a #
# for commentary and a ; for parts of the config file that you
# may wish to enable
#
# NOTE: Whenever you modify this file you should run the command
# "testparm" to check that you have not made any basic syntactic
# errors.
#
#======================= Global Settings =======================
[global]
## Browsing/Identification ###
# Change this to the workgroup/NT-domain name your Samba server will part of
workgroup = WORKGROUP
display charset = UTF8
unix charset = UTF8
encrypt passwords = true
# server string is the equivalent of the NT Description field
server string = %h server (Samba, Ubuntu)
# Windows Internet Name Serving Support Section:
# WINS Support - Tells the NMBD component of Samba to enable its WINS Server
; wins support = no
# WINS Server - Tells the NMBD components of Samba to be a WINS Client
# Note: Samba can be either a WINS Server, or a WINS Client, but NOT both
; wins server = w.x.y.z
# This will prevent nmbd to search for NetBIOS names through DNS.
dns proxy = no
# What naming service and in what order should we use to resolve host names
# to IP addresses
; name resolve order = lmhosts host wins bcast
#### Networking ####
# The specific set of interfaces / networks to bind to
# This can be either the interface name or an IP address/netmask;
# interface names are normally preferred
; interfaces = 127.0.0.0/8 eth0
# Only bind to the named interfaces and/or networks; you must use the
# 'interfaces' option above to use this.
# It is recommended that you enable this feature if your Samba machine is
# not protected by a firewall or is a firewall itself. However, this
# option cannot handle dynamic or non-broadcast interfaces correctly.
; bind interfaces only = true
#### Debugging/Accounting ####
# This tells Samba to use a separate log file for each machine
# that connects
log file = /var/log/samba/log.%m
# Cap the size of the individual log files (in KiB).
max log size = 1000
# If you want Samba to only log through syslog then set the following
# parameter to 'yes'.
; syslog only = no
# We want Samba to log a minimum amount of information to syslog. Everything
# should go to /var/log/samba/log.{smbd,nmbd} instead. If you want to log
# through syslog you should set the following parameter to something higher.
syslog = 0
# Do something sensible when Samba crashes: mail the admin a backtrace
panic action = /usr/share/samba/panic-action %d
####### Authentication #######
# "security = user" is always a good idea. This will require a Unix account
# in this server for every user accessing the server. See
# /usr/share/doc/samba-doc/htmldocs/Samba3-HOWTO/ServerType.html
# in the samba-doc package for details.
; security = share
# You may wish to use password encryption. See the section on
# 'encrypt passwords' in the smb.conf(5) manpage before enabling.
encrypt passwords = true
# If you are using encrypted passwords, Samba will need to know what
# password database type you are using.
passdb backend = tdbsam
obey pam restrictions = yes
105,0-1 19%
obey pam restrictions = yes
; guest account = nobody
; invalid users = root
# This boolean parameter controls whether Samba attempts to sync the Unix
# password with the SMB password when the encrypted SMB password in the
# passdb is changed.
unix password sync = yes
# For Unix password sync to work on a Debian GNU/Linux system, the following
# parameters must be set (thanks to Ian Kahan <<kahan@informatik.tu-muenchen.de> for
# sending the correct chat script for the passwd program in Debian Sarge).
passwd program = /usr/bin/passwd %u
passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully*
.
# This boolean controls whether PAM will be used for password changes
# when requested by an SMB client instead of the program listed in
# 'passwd program'. The default is 'no'.
pam password change = yes
# This option controls how nsuccessful authentication attempts are mapped
# to anonymous connections
map to guest = bad user
########## Domains ###########
# Is this machine able to authenticate users. Both PDC and BDC
# must have this setting enabled. If you are the BDC you must
# change the 'domain master' setting to no
#
; domain logons = yes
#
# The following setting only takes effect if 'domain logons' is set
# It specifies the location of the user's profile directory
# from the client point of view)
# The following required a [profiles] share to be setup on the
# samba server (see below)
; logon path = \\%N\profiles\%U
# Another common choice is storing the profile in the user's home directory
; logon path = \\%N\%U\profile
# The following setting only takes effect if 'domain logons' is set
# It specifies the location of a user's home directory (from the client
104,4 33%
# The following setting only takes effect if 'domain logons' is set
# It specifies the location of a user's home directory (from the client
# point of view)
; logon drive = H:
; logon home = \\%N\%U
# The following setting only takes effect if 'domain logons' is set
# It specifies the script to run during logon. The script must be stored
# in the [netlogon] share
# NOTE: Must be store in 'DOS' file format convention
; logon script = logon.cmd
# This allows Unix users to be created on the domain controller via the SAMR
# RPC pipe. The example command creates a user account with a disabled Unix
# password; please adapt to your needs
; add user script = /usr/sbin/adduser --quiet --disabled-password --gecos "" %u
########## Printing ##########
# If you want to automatically load your printer list rather
# than setting them up individually then you'll need this
; load printers = yes
# lpr(ng) printing. You may wish to override the location of the
# printcap file
; printing = bsd
; printcap name = /etc/printcap
# CUPS printing. See also the cupsaddsmb(8) manpage in the
# cupsys-client package.
; printing = cups
; printcap name = cups
############ Misc ############
# Using the following line enables you to customise your configuration
# on a per machine basis. The %m gets replaced with the netbios name
# of the machine that is connecting
; include = /home/samba/etc/smb.conf.%m
# Most people will find that this option gives better performance.
# See smb.conf(5) and /usr/share/doc/samba-doc/htmldocs/Samba3-HOWTO/speed.html
# for details
# You may want to add the following on a Linux system:
# SO_RCVBUF=8192 SO_SNDBUF=8192
146,1 47%
# You may want to add the following on a Linux system:
# SO_RCVBUF=8192 SO_SNDBUF=8192
socket options = TCP_NODELAY
# The following parameter is useful only if you have the linpopup package
# installed. The samba maintainer and the linpopup maintainer are
# working to ease installation and configuration of linpopup and samba.
; message command = /bin/sh -c '/usr/bin/linpopup "%f" "%m" %s; rm %s' &
# Domain Master specifies Samba to be the Domain Master Browser. If this
# machine will be configured as a BDC (a secondary logon server), you
# must set this to 'no'; otherwise, the default behavior is recommended.
; domain master = auto
# Some defaults for winbind (make sure you're not using the ranges
# for something else.)
; idmap uid = 10000-20000
; idmap gid = 10000-20000
; template shell = /bin/bash
# The following was the default behaviour in sarge,
# but samba upstream reverted the default because it might induce
# performance issues in large organizations.
# See Debian bug #368251 for some of the consequences of *not*
# having this setting and smb.conf(5) for details.
; winbind enum groups = yes
; winbind enum users = yes
# Setup usershare options to enable non-root users to share folders
# with the net usershare command.
# Maximum number of usershare. 0 (default) means that usershare is disabled.
; usershare max shares = 100
# Allow users who've been granted usershare privileges to create
# public shares, not just authenticated ones
usershare allow guests = yes
#======================= Share Definitions =======================
# Un-comment the following (and tweak the other settings below to suit)
# to enable the default home directory shares. This will share each
# user's home directory as \\server\username
;guest ok = yes
189,1 62%
;guest ok = yes
;guest account = root
;[home]
;comment = Home Directories
;browseable = yes
;writable = yes
[root]
comment = root
path = /
writable = yes
browseable = yes
;guest ok = yes
[midow]
comment = midow
path = /home/midow
writable = yes
browseable = yes
# By default, the home directories are exported read-only. Change the
# next parameter to 'no' if you want to be able to write to them.
; read only = no
# File creation mask is set to 0700 for security reasons. If you want to
# create files with group=rw permissions, set next parameter to 0775.
; create mask = 0775
# Directory creation mask is set to 0700 for security reasons. If you want to
# create dirs. with group=rw permissions, set next parameter to 0775.
; directory mask = 0775
# By default, \\server\username shares can be connected to by anyone
# with access to the samba server. Un-comment the following parameter
# to make sure that only "username" can connect to \\server\username
# This might need tweaking when using external authentication schemes
; valid users = %S
# Un-comment the following and create the netlogon directory for Domain Logons
# (you need to configure Samba to act as a domain controller too.)
;[netlogon]
; comment = Network Logon Service
232,0-1 76%
;[netlogon]
; comment = Network Logon Service
; path = /home/samba/netlogon
; guest ok = yes
; read only = yes
; share modes = no
# Un-comment the following and create the profiles directory to store
# users profiles (see the "logon path" option above)
# (you need to configure Samba to act as a domain controller too.)
# The path below should be writable by all users so that their
# profile directory may be created the first time they log on
;[profiles]
; comment = Users profiles
; path = /home/samba/profiles
; guest ok = no
; browseable = no
; create mask = 0600
; directory mask = 0700
[printers]
comment = All Printers
browseable = no
path = /var/spool/samba
printable = yes
guest ok = no
read only = yes
create mask = 0700
# Windows clients look for this share name as a source of downloadable
# printer drivers
[print$]
comment = Printer Drivers
path = /var/lib/samba/printers
browseable = yes
read only = yes
guest ok = no
# Uncomment to allow remote administration of Windows print drivers.
# Replace 'ntadmin' with the name of the group your admin users are
# members of.
; write list = root, @ntadmin
# A sample share for sharing your CD-ROM with others.
;[cdrom]
; comment = Samba server's CD-ROM
275,1 90%
; write list = root, @ntadmin
# A sample share for sharing your CD-ROM with others.
;[cdrom]
; comment = Samba server's CD-ROM
; read only = yes
; locking = no
; path = /cdrom
; guest ok = yes
# The next two parameters show how to auto-mount a CD-ROM when the
# cdrom share is accesed. For this to work /etc/fstab must contain
# an entry like this:
#
# /dev/scd0 /cdrom iso9660 defaults,noauto,ro,user 0 0
#
# The CD-ROM gets unmounted automatically after the connection to the
#
# If you don't want to use auto-mounting/unmounting make sure the CD
# is mounted on /cdrom
#
; preexec = /bin/mount /cdrom
; postexec = /bin/umount /cdrom
;[midow]
;comment = midow samba
;path = /scratchbox/
;writeable = yes
;browsable = yes
;quest ok = no
;create mask = 0644
;directory mask = 0755

user 계정 추가

adduser 계정명
useradd -m 계정명 -G 그룹명

참고로 adduser는 비슷한 기능인데 useradd 명령이 더 low level 이다. debian은 adduser 명령을 쓴다.

user 계정 삭제

관리자 권한으로 다음 명령을 실행한다.

# cd /usr/sbin
./userdel username // username은 유저계정명을 입력한다.

이렇게 지우면 계정의 home directory는 남게되는데 다음 방법으로 모두 계정 정보를 모두 삭제할 수 있다.

deluser --remove-home cool // home directory를 포함해서 지우기
deluser --remove-all-files cool // 계정과 관련된 모든 정보를 지우기

폴더구조 복사하기

$ cd {복사될 소스의 위치}
$ find . -type d -depth | cpio -dumpl {타켓디렉토리주소}

Partition 나눈 device disk 자동으로 mout하기

fstab은 system booting 시 읽어들이는 partition 정보를 담고 있다

vi /etc/fstab

다음을 추가한다.

/dev/sda6 /media/disk ext3 defaults 0 1

vi editor

Tue, 12 Jan 2010 09:06:14 +0900

vi editor의 이해

vi editor는 크기 아래의 3가지 모드로 구성됨

명령모드
입력모드
편집모드

명령모드 단축키

key	Function
i	커서의 현재 위치에서 편집모드로 전환
u	되돌리기, 명령취소
ctrl + r	되살리기
v	블록지정
ctrl + v	사각형 형태로 블록지정

명령모드

문자열 치환하기

:[범위]/[매칭 문자열]/[치환 문자열]/[행 범위]

예를 들어 문서 전체에서 old라는 문자열을 new로 치환하려는 경우 아래와 같이 명령을 입력함

:%s/old/new/g

2행과 4층 사이에서 위와 같이 매칭을 하려는 경우는 아래와 같이 입력함

:%2,4s/old/new/g

현재 커서에서 위로 2행 아래로 3행되는 범위의 문자열을 치환하려는 경우 아래와 같이함

:%-2,+3s/old/new/g

마지막 명령의 'g'를 쓰지 않으면 한 행에 대해서 첫번째 것만 치환하게 됨

마지막 명령에 'c'를 붙이면 치환시 마다 사용자에게 변환할 것인지를 물어봄

아래 명령은 pattern을 이용해서 취환하는 방법을 보여주고 있음

:g/[pattern]/s/new/g

vimrc reference

사용자 root directory에 .vimrc 파일이 존재하면 vim은 실행시에 이를 참조해서 형식을 조정한다.

여기에 vimrc 내용을 참고로 남긴다.

syntax on
set showmatch
set background="dark"
"set number
set hlsearch
"set expandtab
"set ts=4
"set sw=4
"set laststatus=4
"set nocompatible
"set backspace=2
"set autoindent
"set smartindent
""set textwidth=76
set nobackup
set novisualbell
set nojoinspaces
set ruler
set shiftwidth=4
set keywordprg=edic
set showcmd
set incsearch
set autowrite
set title

Snow Leopard

Tue, 12 Jan 2010 01:48:34 +0900

로그인 창에서 기타... 옵션을 삭제하고 나의 계정만 보기

일단 자동로그인이 설정되어 있으면 로그인 창이 안뜨므로 자동로그인을 비활성화 한다.
- 시스템 환경설정 > 계정 > 로그인 옵션 > 자동 로그인 항목을 비활성화됨 선택
사용할 수 있는 계정이 오직 하나 뿐이면 로그인 창에서 바로 패스워드 입력할 수 있게된다. 즉 내가 사용하는 계정 이외는 계정은 모두 삭제한다.
- 방문자 계정이 있다면 시스템 환경설정 > 계정 에서 모두 삭제한다.
- root 계정이 활성화 되어 있다면 응용 프로그램 폴더의 유틸리티 폴더 내에 있는 디렉토리 유틸리티를 실행한다.
  - 메인 메뉴의 편집 > Root 사용자 비활성화를 선택한다.

.profile

리눅스의 .bashrc 에 해당하는 파일이다.

alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'

alias ls='ls -vG'
alias ll='ls -vGla'
alias grep='grep --color'
export LSCOLORS="ExGxcxdxbxegedabagacad"

export PS1='[\u@\h:\w]\$ '

Mouse Tracking 속도 변경하기

터미널을 열고 다음을 입력한다.

defaults write -globalDomain com.apple.mouse.scaling -float 7.4 // 7.5가 필자가 가장 편한 속도였음

로그아웃 - 로그인 한다

좀 더 시각적으로 할 수도 있다.

터미널을 열고 다음을 입력한다.

open ~/Library/Preferences/.GlobalPreferences.plist

그럼 Property List Editor가 뜨면서 .GlobalPreferences.plist가 열린다.

com.apple.mouse.scaling 항목을 찾아서 적당한 숫치로 입력한다.

로그아웃-로그인 한다

만약 다시 시스템 패널을 열고 마우스 tracking 속도를 수정한다면 기본값으로 돌아오니 주의.

WebGL

Mon, 04 Jan 2010 10:05:25 +0900

What is WebGL?

WebGL은 3D graphic을 표현하기 위한 웹 표준 기술이다.

지금까지의 Web은 단지 2차원 평면의 이미지 정보 혹은 텍스트 정보를 표현하는데 만족했지만 Web 기술이 발전함에 따라 막강한 computing power를 요하는 대표적인 기능인 3차원 그래픽 표현 역시 Web contents 상에서 구현이 가능하게 되었다.

현재 Web content를 기술하는 표준 기술로는 HTML, CSS, JavaScript 이렇게 3가지다. 그리고 3차원 그래픽을 기술하는 업계 표준 기술은 OpenGL 이다. WebGL은 Web의 프로그래밍 언어인 JavaScript에 OpenGL을 API를 바인딩한 기술로 한창 표준화 작업 중인 HTML5 Canvas feature로 포함될 것이다.

사실 Web에서 3차원 그래픽을 표현하는 방법이 WebGL 이전에 없었던 것은 아니다.

Adobe의 Flash 기술로도 가능하며, 구글이 공개한 O3D 플러그인으로도 구현할 수 있다.

하지만 이런 기술과 달리 WebGL은 HTML5에 포함될 표준 web기술 이라는 점에서 3차원 그래픽을 표현하는 바람직한 방향이라하겠다.

본 문서는 현재(2010.1.4) WebGL 표준 문서를 기반으로 작성되었다.

Context Creation and Drawing Buffer Presentation

The canvas Element

The Drawing buffer

WebGLRendering Context Object로 이미지를 그리기 전에 Framebuffer를 정의해줘야한다.

이때 Frame Buffer의 크기는 HTMLCanvasElement의 atrribute 중 Width, height를 가지고 결정할 수 있다. 만약 도중에 width, height가 변경이 되면 buffer의 크기가 갱신되고 그 안의 내용은 0,0,0,0 으로 초기화 될 것이다.

기본적으로 drawing buffer는 RGBA color buffer이고 각 색상별 8bit 이상, Depth buffer는 최소 16bits다. 하지만 WebGLContextAtributes object로 이 값을 변경할 수 있지만 getContext()가 처음 호출될때만 가능하며 한번 Context가 만들어지고 나면 변경이 불가함

Open Source License

Fri, 18 Dec 2009 13:54:33 +0900

Open Source License의 이해

Free Software Software

모든 소프트웨어는 공유되어야 한다.
자유로운 사용권보장에 초점을 맞추어 윤리적, 철학적 측면의 자유를 강조
오픈 소스를 가져다 쓰되, 가져다 써 이를 개선했다면 개선된 부분도 모두 공유하여 누구나 사용할 수 있도록 하라는 주의(Copyleft)
Richard Stallman

Open Source Software

Nescape사가 Communicator의 소스코드를 공개한 이후 1990년대 후반에 새롭게 등장하게 된 용어
소스코드를 공개함으로써 얻게되는 기술적인 발전 및 경제적 이점을 강조
가져다 쓰고, 이를 개선하여 별도의 저작물을 만들었다면 이는 공개하지 않아도 됨
Copyleft에서 출발하지만, Copyright인 저작권 등 지적재산권도 일부 일정하는 개념
Eric Raymond, Broce Perens

Software License

저작권을 가진 권리자가 일반 사용자에게 일정 비용을 받고 사용 권한을 부여하는 형태

Opensource License

오픈 소스 개발자와 사용자간의 사용방법 및 조건의 범위를 명시한 계약

오픈 소스 소프트웨어 라이선스가 요구하는 조건을 준수하지 못하면 라이선스를 위반함과 동시에 저작권침해에 해당하고, 최악의 경우 저작권침해소송을 제기당할 수도 있다.

Open Source Definition by OSI(Open source initiative)

자유배포
소스코드
2차적 저작물
소스코드 수정의 제한
개인이나 단체에 대한 차별 금지
사용 분야에 대한 제한 금지
라리선스 배포
라이선스 적용상의 동일성 유지
다른 라이선스의 포괄적 수용
라이선스 기술중립성

기타 License

Microsoft Shared Source License

소스 코드공개/사용을 허용
개발자가 추가/변형한 부분을 다시 Microsoft에게 모든 권리를 넘길 것을 요구
원천적으로 모든 개발 결과물의 소유권은 MS가 갖고, 재배포 권리 또한 인정하지 않음.

Sun Community Source License

누구든 소스 코드 기분 가능, 단 SUN이 자체적으로 정의한 기준에 부합하여야 함.
재배포 역시 SUN에 Royalty를 지불하여야만 가능
현재 SUN은 OSD(Open Source Definitions)기준에 부합하는 라이선스도 갖고 있기때문에 어떤 라이선스인지 확인 필요

Netscape Public License

Netscape사에 대해서만 특권부여 : 수정(개작)시 다른 라이선스 적용가능
Third Party와의 계약상 제약을 피하기 위해 Netcape가 자체 제작한 라이선스

GPL

배경

1980년대 초 PC등의 보급으로 소프트웨어의 상업성이 강조
- AT&T가 UNIX에 대한 권리를 주장
Rechard Stallman이 Free Software Foudation 설립
- 소프트웨어의 자유로운 사용, 공유, 수정을 강조
- 이를 담보하기 위한 장치로 GPL 고안
전세계 자유소프트웨어 개발자들의 GPL 채택
- 1990년대 초 Linux Kernel이 GPL로 배포

의무사항

소스 코드 배포시

저작권 표시
No Warranty
GPL로 배포

실행 파일 배포 시

저작권 표시
No Warranty
GPL로 배포
소스 코드 제공

수정코드 배포 시

저작권 표시
No Warranty
GPL로 배포
소스코드 제공
수정사실 및 일자

소드 코드 공개방식

Object 파일 및 실행파일 배포 시 소스 코드를 함께 제공
최소 3년 동안, 이용자가 요청할 경우 소스코드를 제공하겠다는 문서를 배포하는 방식
웹 상에서 다운 받을 수 있도록 하는 것도 인정

GLP compliance 감시 단체

Free Software Foundation(FSF)
GPL Violations.org(gpl-violations.org)
Software Freedom Law Center(SFLC)

LGPL

Lesser GPL (처음에는 Library GPL로 사용하다 v2.1에서 Lesser GPL로 명칭 변경)

Library에 주로 적용

상용 SW와의 링크를 허용함

LGPL 소스 코드 제공 범위

공개

Original LGPL Library
Work based on the Library
- 수정된 library 전체를 LGPL로 공개
- 파일을 수정했다는 사실과 수정일자 명시

비공개

Independent and Separate Works
- 메모리상에서 독립적으로 실행되는 별도의 저작물
Mere Aggregation
- 동일한 매체에 저장되어 배포되는 독립된 프로그램
Work that uses the Library
- LGPL library를 이용한 응용프로그램

핵심사항 정리

LGPL Library의 일부를 수정한 경우, 수정한 library를 LGPL에 의해 소스코드 공개
LGPL Library에 응용 프로그램을 링키시킬 경우, 해당 응용 프로그램의 소스코드 공개 불필요
LGPL Library와 LGPL이 적용되지 않는 다른 Library의 링크도 가능
LGPL Library를 Static Linking시에는 응용 프로그램의 Object Code를 제공 요
LGPL의 특허권은 GPL과 동일

GPL v3

Tivoization

copyleft SW를 사용하는 제품을 만들어 사용자에게 소스코드를 제공하지만, 사용자가 수정한 SW를 해당 HW상에서 동작시키는 것을 방지하는 행위

Conveying Non-Source Forms 6조 추가

GPL 코드를 특정한 사용자 제품에 포함시키거나 혹은 그와 함께 배포하는 경우에는 해당 소스의 설치 정보를 함께 제공해야 함

Anti-DRM

콘텐츠 제공자의 권리와 이익을 안전하게 보호하기 위해 적법한 사용자만 허용된 사용권한에 따라 콘텐츠를 사용하도록 하는 기술

Protecting User'Legal Rights From Anti-Circurmavention Law 3조 추가

오픈 소스 라이선스 공개 범위 정리

	GPL	LGPL	BSD	MPL	EPL	QPL/상용QT
코드 무료 이용	가능	가능	가능	가능	가능	가능/불가
코드의 자유 배포	가능	가능	가능	가능	가능	가능/불가
소스코드의 공개	공개	공개	비공개	공개	공개	공개/비공개
소스코드의 수정	가능	가능	가능	가능	가능	가능/가능
수정코드의 소스 공개	공개	공개	비공개	공개	공개	공개/비공개
상용 소프트웨어와의 링크	불가	가능	가능	가능	가능	불가/가능

BSD(Berkely Software Distribution)

프로그램의 자유로운 사용, 복제, 배포, 수정을 허용
수정 프로그램에 대한 소스코드 공개 의무 없음, 따라서 상용 소프트웨어에서 무제한 사용 가능
단 아래와 같은 것을 명시해야함

MPL(Mozilla Public License)

Netscape사가 Netscape browser source code를 공개하면서 알

기본 원칙

프로그램의 자유로운 사용, 복제, 배포, 수정 허용

의무사항

저작권 표시
No Warranty
MPL로 배포
Exhibit A의 공지사항 표지
- Original code
- 최초 개발자
- Contributors
소스 코드 제공
- GPL과 BSD의 중간 범위

소스 코드 제공범위

공개

MPL이 적용된 code(Covered Code)

Original code 또는 Modifications 또는 Original Code와 Modification의 결함

원본 소스파일에서 소스코드의 일부분 변경
원본 소스파일의 코드 일부분을 복사하여 새로운 파일을 생성
워논 소스파일의 이름을 변경하거나 두개 이상의 파일을 결합하여 새로운 파일을 생성

비공개

새롭게 추가된 File들
Original code나 수정된 Code의 어떤 부분도 포함하지 않는 새로운 파일을 추가하는 것은 공개할 필요 없음
기본 MPL의 Covered Code와 기타 다른 code를 결합한 프로그램
MPL이 아닌 다른 상용라이선스로 배포가능
MPL코드 이외의 소스는 비공개 가능

MPL 특허권

Licensor의 특허인 경우

MPL에 의해 프로그램을 배포하기 위해서는 라이선스도 함께 부여해야 함

제3자의 특허인 경우

MPL로 배포되는 SW에 제 3자가 특허가 포함되어 있는 경우

LEGAL 파일에 관련 내용을 기록한 후 배포
프로그램을 배포한 후에 특허포함 사실을 안 경우 LEGAL 파일을 변경하고 메일링 리스트나 뉴스그룹을 통해 즉시 알림

Licensee의 특허인 경우

MPL SW를 사용하는 이용자가 특허권을 가지고 있는 경우

Licensee가 소송을 제기하는 경우 라이선스가 자동 종료

그동안 사용했던 부분에 대한 로열티 산정으로 보복조치

QPL

Q(t) Public License

기본 원칙

Trolltech에 의해 배포된 전체 패키지를 수정하지 않은 형태로 복제하거나 배포가능

의무 사항

SW 수정한 경우

패치와 같이 분리된 형태로 배포가능
최초 개발자에게 Royalty-free의 라이선스 부여

QPL SW를 링크하여 응용프로그램을 작성한 경우

응용프로그램 배포 시 완전한 소스코드 제공(QPL SW와 링크된 경우)
응용프로그램의 자유로운 재배포를 허용할 것
최초 개발자가 요청시 Copy본 제공

EPL

Eclipse Public License

2004년 12월 31일자까지 CPL(Common Public License)

CPL에 비해 특허무효조항이 완화됨

라이선스 비교범위(소스코드 공개범위)

GPL, QPL(Modified & Linked SW 전체) > LGPL(Library 단위), EPL(Module 단위) < MPL(File 단위)

주요 의무조항에 따른 분류

주요 의무조항	오픈 소스 라이선스
소스코드 상의 copyright 및 라이선스 관련 문구만 유지	MIT license zlib/libpng
소스코드 공개	GPL, LGPL QPL, MPL, EPL
매뉴얼 내 라이선스전문 포함	GPL, LGPL, QPL Apache 1.1 Apache License 2.0 OpenSSL Vovida Software License BSD
매뉴얼 내 Acknowledgement 표기	Apache 1.1 OpenSSL PHP 3.0
매뉴얼 내 해당 SW명 명시	GPL, LGPL, MPL

Java

Wed, 09 Dec 2009 14:51:21 +0900

Java언어의 자료형

Type	Size
byte	1
short	2
int	4
long	8
char	2
float	4
double	8
boolean	?

byte < short, char < int < long < flaot < double
down casting을 허락하지 않는게 자바언어이기 때문에 이것이 필요하면 명시적 형변환을 한다. (즉 c언어에 있는 암시적 형변환이 없는 것임)
byte 타입을 연산하면 그 결과는 int형이 된다

byte a = 10, b = 20;
byte a = b + c; // Error! b + c의 결과는 int가 되고 이를 더 작은 size 단위인 byte에 대입하는 것은 문법 error다.

Java 기초 문법

final 변수를 사용하면 단 한번 초기화가 가능함

final double pi;
pi = 3.14;
pi = 3.1415 // Error!

for loop 안에서 순차적인 index 접근하는 방법

class ForExample5 {
    public static void main(String args[])
    {
        int arr[] = {10, 20, 30, 40, 50};
        for (int num : arr ) {
            System.out.println(num);
        }
        System.out.println("Don.");
    }
}

try/catch/finally의 사용

finally문

try 문 진입 이후에 exception이 발생하던 안하면 반드시 실행되어야하는 문장이 있다면 이를 finally로 실행한다.

Exception의 상속관계

FNFE < IOException < Exception

Exception이 가장 상위의 부모 클래스다

그래서 catch문의 순서가 중요한데 다음과 같이 검사를 해야 유효한 catch 문이 된다

try
{ ... }
catch (FNFE)
{ ... }
catch (IOException)
{ ... }
catch (Exception)
{ ... }
finally
{ ... }

#include or @import 같은 전처리기가 없다

Java 언어에는 virtual machine이 동작하고있기에 필요한 Class나 형타입의 뭔가가 필요하다가 필요할 때 동적으로 바인딩한다.

this를 이용한 생성자 호출이 가능하다

class Example {
Example(String a, String b)
{
}
Example(String a)
{
this(a, "test");
}
}

하지만 주의할 것이 있는데 this를 이용한 생성자 호출이 다른 멤버변수 혹은 method 호출 이후에 올수는 없다, 즉 아래와 같은 경우는 문법 오류다

Example(String a)
{
this.name = a;
this(a, "test"); // Error!
}

Class 안에서 static 변수는 class로 부터 파생되는 instance 간에 공유되는 자원이다.

Java 언어 에서의 상수 표현

class A {
final static int CONSTANT_VARIABLE = 100;
...
}

클래스 상속의 표현

class CheckingAccount extends Account {
}

부모 클래스의 생성자와 부모 클래스의 private data는 상속 대상이 아니다. 그래서 child class를 초기화할 때 default 생성자가 필요한데 parent가 될 가능성이 있는 class는 default 생성자를 하나 만들어 놓는 것을 권장한다.

final

class 구현이 완료되어 이 class로 부터 새로운 child class를 파생할 수 없다는 것을 명시적으로 나타낼 때 사용한다.

final class Account {

...
}

다른 용례로는 method의 overwriting을 막는데도 사용할 수 있다.

abstract

이 keyword를 쓰면 해당 클래스로 부터 instance를 만들어 낼 수 없다. 즉 추상 클래스로만 존재하고 오로지 상속을 위해서만 사용할 수 있다.

abstract class Account {
...
}

System.gc()

이 함수로 JVM에게 garbage collecting을 요청할 수 있다.

Coding Style Guideline

Tue, 24 Nov 2009 12:20:48 +0900

Code Style Guildline을 정의 / 정리한다.

이 가이드라인은 Apple사의 Coding style for Cocoa 와 Webkit coding style guideline에 기반했다.

Tools

Tue, 17 Nov 2009 11:35:11 +0900

SecureCRT

SecureCRT에서 한글 깨지는 문제

아래 2가지 사항을 확인하고 적용한다.

options > session