thebestolz.blogg.se - Unix executable file converter

$ vi print.iĮxtern FILE *popen (_const char *_command, _const char *_modes) Įxtern char *ctermid (char *_s) _attribute_ ((_nothrow_)) Įxtern void flockfile (FILE *_stream) _attribute_ ((_nothrow_)) Įxtern int ftrylockfile (FILE *_stream) _attribute_ ((_nothrow_)) Įxtern void funlockfile (FILE *_stream) _attribute_ ((_nothrow_))

Now, lets open print.i file and view the content. The preprocessed output is stored in the temporary file that has the extension. So when we compile the program print.c with -save-temps flag we get the following intermediate files in the current directory (along with the print executable) $ ls ‘-save-temps’ flag instructs compiler to store the temporary intermediate files used by the gcc compiler in the current directory. $ gcc -Wall -E print.cĮven better, you can use flag ‘-save-temps’ as shown below. To understand preprocessing better, you can compile the above ‘print.c’ program using flag -E, which will print the preprocessed output to stdout. In this stage the following tasks are done: This is the very first stage through which a source code passes. Now that we have a basic idea about how gcc is used to convert a source code into binary, we’ll review the 4 stages a C program has to go through to become an executable.

Note: When you are working on a big project that contains several C program, use make utility to manage your C program compilation as we discussed earlier. If you don’t specify -o, by default C compiler will create the executable with name a.outįinally, execute print which will execute the C program and display hello world.

-o print – Instruct C compiler to create the C executable as print.

W stands for warning, and we are passing “all” to -W.

-Wall – gcc flag that enables all warnings.

Now, lets run gcc compiler over this source code to create the executable. * Using a macro to print 'Hello World'*/ In Part-I of this article series, we will discuss the steps that the gcc compiler goes through when a C program source code is compiled into an executable.īefore going any further, lets take a quick look on how to compile and run a ‘C’ code using gcc, using a simple hello world example. The four stages for a C program to become an executable are the following: There are four main stages through which a source code passes in order to finally become an executable. Have you ever wondered what happens during the compilation process and how the C program gets converted to an executable? You write a C program, use gcc to compile it, and you get an executable.