inode(7) Miscellaneous Information Manual inode(7) inode - inode inode . stat(2) ( ) stat statx(2) statx. inode stat(2) statx(2): inode stat.st_dev statx.stx_dev_minor statx.stx_dev_major inode ( ) . ( ) ( ). inode stat.st_ino statx.stx_ino inode . inode ( inode ). inode . stat.st_mode statx.stx_mode . stat.st_nlink statx.stx_nlink . link(2). stat.st_uid statx.stx_uid . . chown(2). stat.st_gid statx.stx_gid inode . set-group-ID ( ). chown(2). inode stat.st_rdev statx.stx_rdev_minor statx.stx_rdev_major (inode) inode . stat.st_size statx.stx_size ( ) . . / stat.st_blksize statx.stx_blksize "" / . ( -- .) stat.st_blocks statx.stx_blocks 512 ( st_size/512 ). POSIX.1 st_blocks stat . 512 1024. . (atime) stat.st_atime statx.stx_atime . execve(2) mknod(2) pipe(2) utime(2) read(2) ( ). mmap(2) atime . / atime. ( noatime nodiratime relatime mount(8) mount(2).) atime O_NOATIME open(2). () (btime) ( stat) statx.stx_btime . . btime UNIX . (mtime) stat.st_mtime statx.stx_mtime . mknod(2) truncate(2) utime(2) write(2) ( ). mtime . mtime . (ctime) stat.st_ctime statx.stx_ctime . inode ( ). Epoch 1970-01-01 00:00:00 +0000 UTC ( time(7)). XFS JFS Btrfs ext4 ( 2.6.23). ext2 ext3 Reiserfs. stat statx . stat(2) statx(2) . stat statx 0. stat.st_mode ( statx(2) statx.stx_mode) . POSIX stat.st_mode S_IFMT ( ) 12 07777 9 (0777) . : S_IFMT 0170000 S_IFSOCK 0140000 socket S_IFLNK 0120000 S_IFREG 0100000 S_IFBLK 0060000 S_IFDIR 0040000 S_IFCHR 0020000 S_IFIFO 0010000 FIFO ( ) : stat(pathname, &sb); if ((sb.st_mode & S_IFMT) == S_IFREG) { /* */ } POSIX st_mode : S_ISREG(m) S_ISDIR(m) S_ISCHR(m) S_ISBLK(m) S_ISFIFO(m) FIFO ( ) S_ISLNK(m) ( POSIX.1-1996.) S_ISSOCK(m) ( POSIX.1-1996.) : stat(pathname, &sb); if (S_ISREG(sb.st_mode)) { /* */ } : _BSD_SOURCE ( glibc 2.19 ) _SVID_SOURCE ( glibc 2.19 ) _DEFAULT_SOURCE ( glibc 2.20 ). S_IFSOCK S_ISSOCK() _XOPEN_SOURCE. S_IFSOCK _XOPEN_SOURCE 500 ( glibc 2.24) _XOPEN_SOURCE _XOPEN_SOURCE_EXTENDED. S_ISSOCK() : _BSD_SOURCE ( glibc 2.19 ) _DEFAULT_SOURCE ( glibc 2.20 ) _XOPEN_SOURCE 500 _POSIX_C_SOURCE 200112L ( glibc 2.24) _XOPEN_SOURCE _XOPEN_SOURCE_EXTENDED. st_mode: S_ISUID 04000 ( execve(2)) S_ISGID 02000 ( ) S_ISVTX 01000 ( ) S_IRWXU 00700 S_IRUSR 00400 S_IWUSR 00200 S_IXUSR 00100 S_IRWXG 00070 S_IRGRP 00040 S_IWGRP 00020 S_IXGRP 00010 S_IRWXO 00007 ( ) S_IROTH 00004 S_IWOTH 00002 S_IXOTH 00001 (S_ISGID) . BSD : S_ISGID. execve(2). (S_IXGRP) /. (S_ISVTX) . POSIX.1-2008. POSIX.1-2001. POSIX.1-1990 S_IFMT S_IFSOCK S_IFLNK S_IFREG S_IFBLK S_IFDIR S_IFCHR S_IFIFO S_ISVTX S_ISDIR() . S_ISLNK() S_ISSOCK() POSIX.1-1996 SVID 4 SUSv2. UNIX V7 ( ) S_IREAD S_IWRITE S_IEXEC POSIX S_IRUSR S_IWUSR S_IXUSR. (stat.st_size statx.stx_size) . 0 /proc /sys 4096 . ( '\0' ). stat(1), stat(2), statx(2), symlink(7) 3 . . : . 6.18 8 2026 inode(7)