简单的C语言加密程序

01	int encryption(char *in_fname, char *pwd, char *out_fname)

02

{

03	FILE *fp_1, *fp_2;

04	register char ch;

05	int i = 0, pwd_length = 0;

06

07	fp_1 = fopen(in_fname, "rb");

08

09	if (fp_1 == NULL) {

10	fprintf(stderr, "cannot open in-file: %s.\n", in_fname);

11	return -1;

12

}

13

14	fp_2 = fopen(out_fname, "wb");

15

16	if (fp_2 == NULL) {

17	fprintf(stderr, "cannot open out-file: %s.\n", out_fname);

18	return -1;

19

}

20

21	pwd_length = strlen(pwd);

22

23	while ( (ch = fgetc(fp_1)) != EOF)

24	fputc(ch ^ pwd[i > pwd_length ? i = 0 : i++], fp_2);

25

26	fclose(fp_1);

27	fclose(fp_2);

28

29

return 0;

30

}