4.2 access函数实例

 1 #include "apue.h"
 2 #include <fcntl.h>
 3 int
 4 main(int argc, char *argv[])
 5 {
 6     if (argc != 2)
 7         err_quit("usage: a.out <pathname>");
 8     if (access(argv[1], R_OK) < 0)
 9         err_ret("access error for %s", argv[1]);
10     else
11         printf("read access OK\n");
12     if (open(argv[1], O_RDONLY) < 0)
13         err_ret("open error for %s", argv[1]);
14     else
15         printf("open for reading OK\n");
16     exit(0);
17 }