1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
/*
* fopen.c
*/
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
FILE *fopen(const char *file, const char *mode)
{
int flags = O_RDONLY;
int plus = 0;
int fd;
while (*mode) {
switch (*mode) {
case 'r':
flags = O_RDONLY;
break;
case 'w':
flags = O_WRONLY | O_CREAT | O_TRUNC;
break;
case 'a':
flags = O_WRONLY | O_CREAT | O_APPEND;
break;
case '+':
plus = 1;
break;
}
mode++;
}
if (plus) {
flags = (flags & ~(O_RDONLY | O_WRONLY)) | O_RDWR;
}
fd = open(file, flags, 0666);
if (fd < 0)
return NULL;
else
return fdopen(fd, mode);
}
|
