C language file read/write operations, C language read/write operations

C language file read/write operations, C language read/write operations

// Kailu garji-blog Park Co., http://www.cnblogs.com/kailugaji/.

1 # include <stdio. h> 
2 # include <stdlib. h> 
3 void main () {
4 int a; 
5 void write (); 
6 void read (); 
7 while (1) {
8 printf ("******************* \ n"); 
9 printf ("1. write \ n "); 
10 printf (" 2. read \ n "); 
11 printf (" 0. exit \ n "); 
12 printf (" ******************* \ n "); 
13 printf (" Please choose: "); 
14 scanf (" % d ", & a); 
15 if (a = 0) {
16 exit (0 ); 
17} 
18 else if (a = 1) {
19 write ();
 20} 
21 else if (a = 2) {
22 read (); 
23} 
24 else
25 printf ("input e Rror! \ NPlease choose: "); 
26} 27
 28} 

29 
30 void write () {
31 FILE * fp; 
32 char ch, filename [20]; 
33 printf ("Please input the filename you want to write:"); 
34 scanf ("% s", filename); 
35 if (! (Fp = fopen (filename, "wt +") {
36 printf ("Cannot open the file! \ N "); 
37 exit (0); 
38} 
39 
40 printf (" Please input the sentences you want to write: "); 
41 ch = getchar (); 
42 ch = getchar (); 
43 while (ch! = EOF) {// EOF: Ctrl + z
44 fputc (ch, fp); 
45 ch = getchar (); 
46} 
47 
48 fclose (fp ); 
49 
50} 
51 
52 void read () {
53 FILE * fp; 
54 char ch, filename [20]; 
55 printf ("Please input the filename you want to read :"); 
56 scanf ("% s", filename);
 57 if (! (Fp = fopen (filename, "r") {
58 printf ("Cannot open the file! \ N "); 
59 exit (0); 
60} 
61 
62 printf (" % s content: ", filename); 
63 while (ch! = EOF) {// EOF (end of file): Ctrl + z
64 ch = fgetc (fp); 
65 putchar (ch); 
66} 
67 
68 fclose (fp); 
69}

Current Directory before running the program:

Program running result:

A file wrr.txt was added to the current directory.

Open the file:

 

The entered content already exists:

Hello world!
I am RONGRONG WANG!
My English name is Kailugaji!
Thank you!