Use Vim to write C language programs in Linux

1. Enter the character page

2. Create a folder to store the source file

Mkdir helloworld // create a folder

CD helloworld // enter the new folder. Here we should say that the directory is better, and Windows is used to it.

Vim main. C // open vim and create the main. c file

// Press the I key to enter the editing status. The following are the programs.

# Include
Int main ()

{

Printf ("Hello world! /N ");

Return 0;

}

Press ESC to Enter command mode, press ZZ to save and exit

GCC main. C // compile

./A. Out // run. The a. out executable file is generated by default.
How to compile a C ++ program in GCC ++ and run the favorites
GCC can compile three languages: C, C ++, and Object C (an object-oriented extension of C ). The GCC command can be used to compile and connect the C and C ++ source programs at the same time.

# DEMO #: Hello. c

If you have two or a few C source files, you can easily use GCC to compile, connect, and generate executable files. For example, if you have two source files main. C and factorial. C, compile a program to calculate factorial.


-----------------------
List factorial. c
-----------------------
# Include <stdio. h>
# Include <stdlib. h>

Int factorial (int n)
{
If (n <= 1)
Return 1;

Else
Return factorial (n-1) * N;
}
-----------------------

-----------------------
Listing main. c
-----------------------
# Include <stdio. h>
# Include <stdlib. h>

Int factorial (int n );

Int main (INT argc, char ** argv)
{
Int N;

If (argc <2 ){
Printf ("Usage: % S n/n", argv [0]);
Return-1;
}
Else {
N = atoi (argv [1]);
Printf ("factorial of % d is % d./N", N, factorial (n ));

}

Return 0;
}
-----------------------

The following command can be used to compile and generate executable files and execute programs:
$ Gcc-O factorial main. c factorial. c
$./Factorial 5
Factorial of 5 is 120.

GCC can be used to compile both C and C ++ programs. Generally, the C compiler uses the extension of the source file to determine whether it is a C program or a C ++ program. In Linux, the extension of the C source file is. C, and the extension of the C ++ source file is. C or. cpp.


However, the GCC command can only compile the C ++ source file, but cannot automatically connect to the library used by the C ++ program. Therefore, the G ++ command is usually used to compile and connect the C ++ program. The program automatically calls GCC for compilation. Suppose we have the following C ++ source file (hello. C ):


# Include <iostream. h>

Void main (void)
{
Cout <"Hello, world! "<Endl;
}

You can call the G ++ command to compile, connect, and generate an executable file as follows:

$ G ++-O hello. c
$./Hello
Hello, world!

1.7.2 main gcc/egcs options
Table 1-3 common GCC commands
Option description
-ANSI only supports the ANSI standard C syntax. This option will disable some features of gnu c,

For example, ASM or typeof keywords.
-C only compiles and generates the target file.
-Dmacro defines the macro with the string "1.
-Dmacro = defn: Define the macro with the string "defn.
-E only runs the C pre-compiler.
-G generates debugging information. The GNU Debugger can use this information.
-Idirectory: specify an additional header file to search for the path directory.
-Ldirectory: specify an additional function library to search for the path directory.
-Search for the specified library when connecting to llibrary.
-Msung optimizes code for 486.
-O file: generate the specified output file. Used to generate executable files.
-O0 is not optimized.
-O or-O1 optimized code generation.
-O2 is further optimized.
-O3 is further optimized than-O2, including the inline function.
-Shared shared object generation. It is usually used to create a shared library.
-Static prohibit the use of shared connections.
-Umacro undefines macro macros.
-W does not generate any warning information.
-Wall generates all warning information.