stat函数使用

stat是非常常用的一个函数，可以获取文件的一些属性，或判断文件的类型。

下面直接取自man 2 stat中的示例代码：

#include <sys/types.h> #include <sys/stat.h> #include <time.h> #include <stdio.h> #include <stdlib.h> int main(int argc, char *argv[]) { struct stat sb; if (argc != 2) { fprintf(stderr, "Usage: %s <pathname>\n", argv[0]); exit(EXIT_FAILURE); } if (stat(argv[1], &sb) == -1) { perror("stat"); exit(EXIT_FAILURE); } printf("File type: "); switch (sb.st_mode & S_IFMT) { case S_IFBLK: printf("block device\n"); break; case S_IFCHR: printf("character device\n"); break; case S_IFDIR: printf("directory\n"); break; case S_IFIFO: printf("FIFO/pipe\n"); break; case S_IFLNK: printf("symlink\n"); break; case S_IFREG: printf("regular file\n"); break; case S_IFSOCK: printf("socket\n"); break; default: printf("unknown?\n"); break; } printf("I-node number: %ld\n", (long) sb.st_ino); printf("Mode: %lo (octal)\n", (unsigned long) sb.st_mode); printf("Link count: %ld\n", (long) sb.st_nlink); printf("Ownership: UID=%ld GID=%ld\n", (long) sb.st_uid, (long) sb.st_gid); printf("Preferred I/O block size: %ld bytes\n", (long) sb.st_blksize); printf("File size: %lld bytes\n", (long long) sb.st_size); printf("Blocks allocated: %lld\n", (long long) sb.st_blocks); printf("Last status change: %s", ctime(&sb.st_ctime)); printf("Last file access: %s", ctime(&sb.st_atime)); printf("Last file modification: %s", ctime(&sb.st_mtime)); exit(EXIT_SUCCESS); }

flying-bird@flyingbird:~/examples/cpp/stat$ ./a.out Usage: ./a.out <pathname> flying-bird@flyingbird:~/examples/cpp/stat$ ./a.out . File type: directory I-node number:  Mode: 40775 (octal) Link count: 2 Ownership: UID=1000 GID=1000 Preferred I/O block size: 4096 bytes File size: 4096 bytes Blocks allocated: 8 Last status change: Tue May 27 19:44:20 2014 Last file access: Tue May 27 19:44:21 2014 Last file modification: Tue May 27 19:44:20 2014 flying-bird@flyingbird:~/examples/cpp/stat$ ./a.out ./a.out File type: regular file I-node number:  Mode:  (octal) Link count: 1 Ownership: UID=1000 GID=1000 Preferred I/O block size: 4096 bytes File size: 7463 bytes Blocks allocated: 16 Last status change: Tue May 27 19:44:20 2014 Last file access: Tue May 27 19:44:22 2014 Last file modification: Tue May 27 19:44:20 2014 flying-bird@flyingbird:~/examples/cpp/stat$ ll /dev/sd sda sda1 sda2 sda3 sda5 sda6 sda7 sdb sdb1 sdb2 sdb5 sdb6 sdb7 sdc sdd sde sdf flying-bird@flyingbird:~/examples/cpp/stat$ ./a.out /dev/sda File type: block device I-node number: 6645 Mode: 60660 (octal) Link count: 1 Ownership: UID=0 GID=6 Preferred I/O block size: 4096 bytes File size: 0 bytes Blocks allocated: 0 Last status change: Tue May 27 18:41:12 2014 Last file access: Tue May 27 18:41:13 2014 Last file modification: Tue May 27 18:41:12 2014 flying-bird@flyingbird:~/examples/cpp/stat$ ./a.out /dev/sda5 File type: block device I-node number: 461 Mode: 60660 (octal) Link count: 1 Ownership: UID=0 GID=6 Preferred I/O block size: 4096 bytes File size: 0 bytes Blocks allocated: 0 Last status change: Tue May 27 18:41:13 2014 Last file access: Tue May 27 18:55:36 2014 Last file modification: Tue May 27 18:41:13 2014 flying-bird@flyingbird:~/examples/cpp/stat$