LinuxC programming (3)-a simple example

LinuxC programming (3)-a simple example-general Linux technology-Linux programming and kernel information. The following is a detailed description. /* Main. c/

# Include "print. h"

Int main (void)

{

Myprint ("hello world! ");

}

Code Description:

Main. c calls a myprint function, which is defined in print. h.

The purpose of calling the myprint function is to print a "hello world !"

Define the header file in print. h.







/* Print. h */

# Ifndef _ MYPRINT_H

# Define _ MYPRINT_H



Void myprint (char * print_str );



# Endif

Code Description:

# Ifndef _ MYPRINT_H: The naming rule for declarative recognition is generally that the header file name is in uppercase, followed by an underscore, and "." In the file name is also underlined.

Implement a simple print and display function.







/* Print. c */

# Include



Void myprint (char * print_str)

{

Printf ("This is my first linux's program: % s \ n", print_str );

}

Code Description:

The myprint function uses the standard output function printf, so the header file includes stdio. h.

(4) use makefile for project management. The contents of makefile are as follows.









Main: main. o myprint. o

Gcc-o main. o myprint. o

Main. o: main. c

Gcc-c main. c

Myprint. o: myprint. c print. h

Gcc-c myprint. c

Code Description:

The base principle of make is "dependency". The executable file main depends on main. o, myprint. o, similarly, main. o depends on main. c, and myprint. o depends on myprint. c and print. h.

Gcc is used to program source files into target files, such as gcc in code? C main. c is to compile main. c into main. o,

Save the source and makefile files in the same folder in Linux, and then run the make compilation link program as follows:

[David @ XUEER ex0101] $ make

Gcc-c main. c

Gcc-o main. o myprint. o

[David @ XUEER ex0101] $./main

This is myfirst linux's progruam: hello world!

So far, this small program is complete.