구차니의 잡동사니 모음

흐음.. 일단은 실패 ㅠㅠ

xfce 쓰기 전에는 답이 없는건가..

ubuntu mate 통해서 하는건 보이긴 한데.. 흐음...

mstsc로 접속

여기서 접속하면 먼가 뜨다가 그냥 창이 닫힌다.. 머가 문제지..

xfce가 아니라 그런가?

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[링크 : http://abydos.tistory.com/3]

cygwin에서

xorg-server 를 설치해야 X가 설치 되는데...

cygwin shell을 통해서

$ X -query ip

입력하면 되긴한데.. 이상하리 만치 무지 느리다.

[링크 : http://x.cygwin.com/docs/ug/using-remote-session.html]

다만.. ubuntu 15.10 + Xming on win10 은 오류가 나는데

Cygwin/X는 오류는 나지 않는다는 차이?

2009/03/24 - [프로그램 사용/cygwin / Xming] - cygwin/x 설치하기

XDMCP로 하니까 무시무시하게 대역폭을 잡아먹네... -_-a

Xming에 Xnest로는 왜이렇게 안되지 -_-??

먼가 자꾸 끊어지는데..

아무튼 로그인에서 Advanced를 누른다.

저장된 경우에는 Edit을 누르면 아래와 같이 활성화 되니 수정후 Save!

AES(기본값) 음.. 14MB 정도일려나?

ARCFOUR 한.. 22MB/s 메가?

[링크 : https://winscp.net/eng/docs/ui_login_ssh]

5.7.1에서 5.7.6으로 바꾸고 나서 하니

AES

15MB/s -> 21MB/s

arcfour

24MB/s -> 50MB/s

암호화 지원하지 않아 안전하지 않다라...

XDMCP is inherently insecure as it does not encrypt your traffic. XDMCP is analogous to telnet, and therefore they share the same security issues. 

[링크 : https://wiki.ubuntu.com/xdmcp]

netsarang의 Xmanager는 XDMCP를 자체 지원하는데..

2단계 거쳐서 하라는거 보면 putty의 X11 포워딩 삘이..

[링크 : https://www.netsarang.com/tutorial/xmanager/3270/title]

아무튼 실험해보니..

putty + Xming으로

arcfour 설정해주니 썩 나쁘지 않은 속도로 반응

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스트림 사이퍼.. 블록이 아니라 더 빠르게 응답하는 걸려나?

[링크 : https://en.wikipedia.org/wiki/RC4]

Update: Ben Harris has written an Internet-Draft (draft-harris-ssh-arcfour-fixes, now RFC 4345) describing a way of using Arcfour reasonably securely with SSH-2, and PuTTY now implements this. Note that this document defines the "arcfour256" and "arcfour128" ciphers; PuTTY still does not support the less secure "arcfour" cipher, and we have no plans to make it do so.

(Support was first added in 2005-04-22, but uonly under private names defined in an earlier draft: "arcfour256-draft-00@putty.projects.tartarus.org" and so on. Only from 2005-09-04 do we support the IETF names, which also appear in OpenSSH from 4.2.)

[링크 : http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/arcfour.html]

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엥 다시 실행해보니..

XDMCP 보다 오히려 arcfour가 빠른 느낌이다 ㄷㄷ

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[링크 : http://linux.die.net/man/1/xnest]

[링크 : http://www.x.org/archive/X11R7.5/doc/man/man1/Xnest.1.html]

[링크 : https://en.wikipedia.org/wiki/Xnest]

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xnest의 사용법의 예제...?

일종의 vm 처럼 보이는 기분 ㅋㅋㅋ

[링크 : http://www.idevelopment.info/data/Unix/Linux/LINUX_ConfiguringXDMCPRedHatLinux.shtml]

속도까지 잰건 아니지만

아무튼.. putty - X11 forwarding - Xming

을 통해서 

Xnest :1 -query localhost

명령 수행시 화면 로딩 속도를 보면

DES, ARCFOUR > AES > 3DES > blowfish

정도의 느낌?

putty에서는 AES가 기본이긴 한데

보안을 희생하고 속도를 올리려면..

ARCFOUR 정도가 무난할지도?

일단 벤치상으로는 arcfour가 가장 빠르고 blowfish가 그걸 뒤따르는데

체감이랑은 좀 많이 다른 듯..

[링크 : http://xmodulo.com/how-to-speed-up-x11-forwarding-in-ssh.html]

2015/09/24 - [프로그램 사용/ssh / scp / sftp] - ssh X11 forwarding 속도 향상

Ubuntu 12.04 LTS 서버측 설정

[링크 : https://wiki.ubuntu.com/xdmcp]

xming 클라이언트 설정(윈도우)

VNC보단 확실히 빠른느낌이다.

나중에 로컬이 아닌 외부에서 시도해봐야지..

XDMCP protocol on port 177/UDP. But the actual X11 protocol connections will be made to the local port 6000+n /TCP, where n is the display-number.

[링크 : http://www.straightrunning.com/XmingNotes/IDH_XDMCP.htm]

Open up TCP port 6000-6005 (plus X-Win32’s base display number) in both directions

Open up UDP port 177 to accept incomming connections from any port.

[링크 : https://www.starnet.com/xwin32kb/what-ports-need-to-be-opened-for-xdmcp/]

2009/04/10 - [프로그램 사용/cygwin / Xming] - Xming XDMCP 관련 도움말

2009/05/19 - [프로그램 사용/cygwin / Xming] - Xming --help

gcc -M을 통해서 해당 소스가 끌어와야 하는 헤더들의 목록을 얻어낼수 있다.

이걸 이용하여 역으로

make 파일에서 사용해야 하는 헤더들의 목록을 생성해 낼 수 있고

이걸 make dep나 make depend를 통해서 수행하게 된다.

생각해보니.. ifdef로 된거.. option 파일이 아닌

-D 인자를 통해서 gcc -M -Dflag 해주면... 외부에서 소스변경없이 구현이 가능해져서 더 편하려나?

[링크 : http://developinghappiness.com/?p=174]

    [링크 : http://developinghappiness.com/?page_id=222]

[링크 : http://linux.die.net/man/1/gccmakedep]

타겟을 만들지 않아도 컴파일 되는 이유... 라고 해야하나?

*.c는 $(CC)를

*.cc나 *.C는 $(CXX)를 이용해서 컴파일 하는데

$(CPPFLAGS) 와 $(CFLAGS)를 인자로 받으니..

여기에 헤더와 링커 경로를 넣어주면 자동으로 알아서 작동하는 마법!

[링크 : http://korea.gnu.org/manual/4check/make-3.77/ko/make_10.html#SEC91]

-E는 프리프로세서를 거친 결과를 뽑아준다면..

-M은 확장된 헤더의 목록만 빼준다.

-E

Stop after the preprocessing stage; do not run the compiler proper. The output is in the form of preprocessed source code, which is sent to the standard output.

-M

Instead of outputting the result of preprocessing, output a rule suitable for make describing the dependencies of the main source file. The preprocessor outputs one make rule containing the object file name for that source file, a colon, and the names of all the included files, including those coming from -include or -imacros command line options.

Unless specified explicitly (with -MT or -MQ), the object file name consists of the name of the source file with any suffix replaced with object file suffix and with any leading directory parts removed. If there are many included files then the rule is split into several lines using \-newline. The rule has no commands.

This option does not suppress the preprocessor's debug output, such as -dM. To avoid mixing such debug output with the dependency rules you should explicitly specify the dependency output file with -MF, or use an environment variable like DEPENDENCIES_OUTPUT . Debug output will still be sent to the regular output stream as normal.

Passing -M to the driver implies -E, and suppresses warnings with an implicit -w.

-MM

Like -M but do not mention header files that are found in system header directories, nor header files that are included, directly or indirectly, from such a header.

This implies that the choice of angle brackets or double quotes in an #include directive does not in itself determine whether that header will appear in -MM dependency output. This is a slight change in semantics from GCC versions 3.0 and earlier.

[링크 : http://linux.die.net/man/1/gcc]

‘warning: jobserver unavailable: using -j1. Add `+' to parent make rule.’

In order for make processes to communicate, the parent will pass information to the child. Since this could result in problems if the child process isn’t actually a make, the parent will only do this if it thinks the child is a make. The parent uses the normal algorithms to determine this (see How the MAKE Variable Works). If the makefile is constructed such that the parent doesn’t know the child is a make process, then the child will receive only part of the information necessary. In this case, the child will generate this warning message and proceed with its build in a sequential manner.

make 프로세스가 통신을 하기 위해서, 부모는 자식에게 정보를 넘겨줄 것이다. 자식 프로세스가 실제로 make를 하지 못하는 문제가 발생하기 전까지, 부모는 자식이 make를 진행 중이라고 생각을 할 것이다. 부모는 이것을 결정하기 위한 일반적인 알고리즘을 사용한다(How the MAKE Variable Works를 볼 것). 만약 makefile이 부모가 자식이 make 프로세스란걸 알지 못 하는 것과 같은 구조로 짜여있을 경우, 자식은 필요한 정보의 일부분만 받게 될 것이다. 이경우, 자식은 이 경고 메시지를 생성하고 자신의 빌드를 순차적인 방법으로 진행할 것이다.

[링크 : https://www.gnu.org/software/make/manual/html_node/Error-Messages.html]

Recursive make commands should always use the variable MAKE, not the explicit command name ‘make’, as shown here:

subsystem:

        cd subdir && $(MAKE)

[링크 : https://www.gnu.org/software/make/manual/html_node/MAKE-Variable.html#MAKE-Variable]

한줄 요약하자면..

병렬 구조로 안짜여졌으니 병렬로 안하겠어! 라는 의미

해결책은..

make -c ... 

이런거 대신

$(MAKE) -c ...

이런식으로 MAKE 변수를 써라.. 인가?

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Only certain flags go into $(MAKEFLAGS).  -j isn't included because the sub-makes communicate with each other to ensure the appropriate number of jobs are occuring

Also, you should use $(MAKE) instead of make, since $(MAKE) will always evaluate to the correct executable name (which might not be make).

[링크 : http://stackoverflow.com/questions/9147196/makefile-pass-jobs-param-to-sub-makefiles]

The ‘-j’ option is a special case (see Parallel Execution). If you set it to some numeric value ‘N’ and your operating system supports it (most any UNIX system will; others typically won’t), the parent make and all the sub-makes will communicate to ensure that there are only ‘N’ jobs running at the same time between them all. Note that any job that is marked recursive (see Instead of Executing Recipes) doesn’t count against the total jobs (otherwise we could get ‘N’ sub-makes running and have no slots left over for any real work!)

If your operating system doesn’t support the above communication, then ‘-j 1’ is always put into MAKEFLAGS instead of the value you specified. This is because if the ‘-j’ option were passed down to sub-makes, you would get many more jobs running in parallel than you asked for. If you give ‘-j’ with no numeric argument, meaning to run as many jobs as possible in parallel, this is passed down, since multiple infinities are no more than one.

If you do not want to pass the other flags down, you must change the value of MAKEFLAGS, like this:

subsystem:

        cd subdir && $(MAKE) MAKEFLAGS=

The command line variable definitions really appear in the variable MAKEOVERRIDES, and MAKEFLAGS contains a reference to this variable. If you do want to pass flags down normally, but don’t want to pass down the command line variable definitions, you can reset MAKEOVERRIDES to empty, like this:

MAKEOVERRIDES =

This is not usually useful to do. However, some systems have a small fixed limit on the size of the environment, and putting so much information into the value of MAKEFLAGS can exceed it. If you see the error message ‘Arg list too long’, this may be the problem. (For strict compliance with POSIX.2, changing MAKEOVERRIDES does not affect MAKEFLAGS if the special target ‘.POSIX’ appears in the makefile. You probably do not care about this.)

A similar variable MFLAGS exists also, for historical compatibility. It has the same value as MAKEFLAGS except that it does not contain the command line variable definitions, and it always begins with a hyphen unless it is empty (MAKEFLAGS begins with a hyphen only when it begins with an option that has no single-letter version, such as ‘--warn-undefined-variables’). MFLAGS was traditionally used explicitly in the recursive make command, like this:

subsystem:

        cd subdir && $(MAKE) $(MFLAGS)

but now MAKEFLAGS makes this usage redundant. If you want your makefiles to be compatible with old make programs, use this technique; it will work fine with more modern make versions too.

[링크 : https://www.gnu.org/.../html_node/Options_002fRecursion.html#Options_002fRecursion]