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tar Tape Archive

Tar used to create archive files in Unix/Unix like systems to make tape backups. Create tar archive tar -cvf my_archive.tar myDirectory c = Create v = Verbose f = File List files in an archive tar -tvf my_archive.tar t = list v = verbose f = file Create tar archive with gzip compression tar -cvzf my_archive.tar.gz myDirectory c = Create v = Verbose z = Gzip Compression f = File Un tar / unzip tar -xvf  my_archive.tar

Compiler, Obect Code / Relocatable Code, Linker

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When we compile a C source file using GNU C compiler, it compiles our code into an assembly source. Then, the assembly source is assembled by the assembler (included with gcc (GNU C compiler)). It generates the object code (relocatable format machine code), and it is usually not directly executable. Next, the linker links libraries. Libraries are also in relocatable format, this is why we compile libraries with -shared / -fpic / -fPIC flags. The linking process checks the library name that we included in the source file and it also checks whether the library is available in the system's default library path /usr/lib (GNU/Linux) if not, we can pass the specific libraries as an argument to gcc with -I flag (gcc -I/home/shuja/Documents/libmy.so )  finally, the linker links our sources(object codes) with libraries and generates the executable. C Source File  Assembly Source (generated  by GNU C compiler) Disassembled object code (Disassembled because object code isn't

Java Byte Code, Interpreter and JIT

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Generally, when a program is compiled to an intermediate level and then interpreted  by a virtual machine, it runs slower than it would run if compiled to machine code. However, with Java, the differential between the two is not important for general purpose. Because byte-codes are highly  optimized, the use of byte-code enables the Java Virtual Machine to execute programs much  faster than you might expect. Java is also designed as an interpreted language, so java does not have anything to stop  (on the fly) compilation of byte-code into machine code, to improve  performance. For this reason, the HotSpot technology was introduced after Java’s initial release. HotSpot provides a Just In Time (JIT) compiler for bytecode. When a JIT compiler is part  of the JVM, selected set of bytecode are compiled into executable code in real time,  on a piece, by, piece, demand basis.  It is important to understand that it is not practical to  compile a whole Java program into machine code all a

No one loved Kingswood more devotedly than he

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During World War I, Kingswood enlisted a group of present boys as cadet officers to fight on behalf of the Crown, the son of a family that was close to Kingswood — Brian Leslie De Vos  — Kingswood For Ever The Story of Kingswood Kandy - Chapter Kingswood and The World War - Page 98  "The thirteenth and last for mention is Brian Leslie de Vos who was wounded in action on the 28th March 1918 and died on the following day of his wounds. No one loved Kingswood more devotedly than he. He was entirely our own; he exulted in being ours and entirely ours. Every letter of his from the Front, to whomever written, had some endearing reference to the school. He was wounded once in France, and wrote afterwards : "I now have in my possession a copy of the Kingswood Song, stained with blood. It was on my person when I was wounded. It is the souvenir I value most. Can you get me the music of the Kingswood Song? Oh! for a Kingswood day again!" He left Kandy on the 18th October 1915.

Department for Persons Registration of Sri Lanka

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Yesterday I went to the Department for Persons Registration to get new NIC for my lost NIC. I reached there at 9.00 AM. I had to stand in a long que for about 30 minutes. Then they gave me a number card and they told that they will call me to the counter according to that number. They called me at 11.30 AM. I paid the fee. When I gave my file I told them, there is a correction to be made in my name. They told me that it is not a problem, we enter your name as it is in the birth certificate. Then I was standing for a long time, and at last they announced my name at 3.30 PM. Finally I got my NIC but my name was not corrected. What they did was, they copied the details from my old NIC and pasted it in the new card. (CTRL+C, CTRL+V)

Connect Huawei Modem Linux - USB Modeswitch

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Generally, if you plugged a USB modem to a Linux, it identifies the modem, as a USB Storage device. So due to that you can't access internet through your USB Modem. So you must change the device identification. For that, you need usb-modeswitch package. if you currently have internet in your system, you can install it easily. First you must check whether the  usb-modeswitch is  already   installed in your system.  For that open Terminal and type sudo usb_modeswitch  . If it already installed in your system the output will be like this.

Install Gammu In Windows

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This tutorial's video is at the bottom of this post. First, download Gammu for Windows. http://wammu.eu/download/gammu/win32/ Then, extract the Files to a Folder. Next, in the Folder, Go to  Gammu-1.30.0-Windows\share\doc\gammu\examples\config Open the "gammuurc" file from Word Pad.  Then you will see as below screen shot.