To see why this complexity actually helps us, we should note that normally the link phase is much faster than the compilation phase. This is especially true when doing optimizations, since that step is done before linking. Now, lets assume we change the source file "a. We'll only need now two commands: cc -c a. Now that we've learned that compilation is not just a simple process, lets try to see what is the complete list of steps taken by the compiler in order to compile a C program.
Driver - what we invoked as "cc". This is actually the "engine", that drives the whole set of tools the compiler is made of. We invoke it, and it begins to invoke the other tools one by one, passing the output of each tool as an input to the next tool.
C Pre-Processor - normally called "cpp". It takes a C source file, and handles all the pre-processor definitions include files, define macros, conditional source code inclusion with ifdef, etc. The C Compiler - normally called "cc1". This is the actual compiler, that translates the input file into assembly language. As you saw, we used the "-c" flag to invoke it, along with the C Pre-Processor, and possibly the optimizer too, read on , and the assembler. Optimizer - sometimes comes as a separate module and sometimes as the found inside the compiler module.
This one handles the optimization on a representation of the code that is language-neutral. This way, you can use the same optimizer for compilers of different programming languages. Assembler - sometimes called "as". This takes the assembly code generated by the compiler, and translates it into machine language code kept in object files. A Common format these days is known as "ELF".
On SunOs systems, and other older systems, a format named "a. This format defines the internal structure of the executable file - location of data segment, location of source code segment, location of debug information and so on.
As you see, the compilation is split in to many different phases. Not all compiler employs exactly the same phases, and sometimes e. But the basic idea is quite similar - split the compiler into many different parts, to give the programmer more flexibility, and to allow the compiler developers to re-use as many modules as possible in different compilers for different languages by replacing the preprocessor and compiler modules , or for different architectures by replacing the assembly and linker-loader parts.
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To run the C program use the command:. This will save the output in the file. To view the file use cat command :. Now you can use C language to create useful programs and then run those programs easily in Linux. Skip to content. Right click the program file and choose Run Code. Program output is displayed in the bottom section of the editor.
Like what you read? Please share it with others. What next?? Policies Affiliate Policy Privacy Policy. Close dialog. Session expired Please log in again. Loading Comments Email Required Name Required Website. Here's some very basic simplified code of my bash script:! How to keep program running after logout. Hello everyone. I am logged into a computer through ssh. I would like to run a program and have it keep running after I log out without screen i forgot to run it. Running C program problem.
Hi All, How to run c program using shell script? Help with Running More than One Program. Folks, I'm really new to scripting and was wondering if you could help me out. I have the following script that I inherited:! Running a program Dynflow. Lets get some stuff out of the way before the question. I am currently running FreeBSD 7. My boss gave me some files that he says are a unix version of the program Dynflow. The Programs Hello, My apologies if this sounds like a stupid question Many thanks rkap 1 Reply.
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