1 5dc21454 2023-07-14 jrmu /*
 2 5dc21454 2023-07-14 jrmu  * 3-2. Write a function escape(s,t) that converts characters like newline
 3 5dc21454 2023-07-14 jrmu  * and tab into visible escape sequences like \n and \t as it copies the
 4 5dc21454 2023-07-14 jrmu  * string t to s. Use a switch. Write a function for the other direction as
 5 5dc21454 2023-07-14 jrmu  * well, converting escape sequences into the real characters.
 6 5dc21454 2023-07-14 jrmu  */
 7 5dc21454 2023-07-14 jrmu 
 8 5dc21454 2023-07-14 jrmu #include <stdio.h>
 9 5dc21454 2023-07-14 jrmu 
10 5dc21454 2023-07-14 jrmu void escape(char s[], char t[]);
11 5dc21454 2023-07-14 jrmu 
12 5dc21454 2023-07-14 jrmu main()
13 5dc21454 2023-07-14 jrmu {
14 5dc21454 2023-07-14 jrmu 	char str[400];
15 5dc21454 2023-07-14 jrmu 	escape (str, "This\t\t\t is a test\n to see\n\t\t if escaping works");
16 5dc21454 2023-07-14 jrmu 	printf("%s\n", str);
17 5dc21454 2023-07-14 jrmu }
18 5dc21454 2023-07-14 jrmu 
19 5dc21454 2023-07-14 jrmu void escape(char s[], char t[]) {
20 5dc21454 2023-07-14 jrmu 	int i, j;
21 5dc21454 2023-07-14 jrmu 	for (i = 0, j = 0; t[j] != '\0'; ++i, ++j) {
22 5dc21454 2023-07-14 jrmu 		switch (t[j]) {
23 5dc21454 2023-07-14 jrmu 			case '\t':
24 5dc21454 2023-07-14 jrmu 				s[i++] = '\\';
25 5dc21454 2023-07-14 jrmu 				s[i] = 't';
26 5dc21454 2023-07-14 jrmu 				break;
27 5dc21454 2023-07-14 jrmu 			case '\n':
28 5dc21454 2023-07-14 jrmu 				s[i++] = '\\';
29 5dc21454 2023-07-14 jrmu 				s[i] = 'n';
30 5dc21454 2023-07-14 jrmu 				break;
31 5dc21454 2023-07-14 jrmu 			default:
32 5dc21454 2023-07-14 jrmu 				s[i] = t[j];
33 5dc21454 2023-07-14 jrmu 				break;
34 5dc21454 2023-07-14 jrmu 		}
35 5dc21454 2023-07-14 jrmu 	}
36 5dc21454 2023-07-14 jrmu 	s[i] = t[j];
37 5dc21454 2023-07-14 jrmu }