statfs, fstatfs - get file system statistics


SYNOPSIS

       #include <sys/vfs.h>

       int statfs(const char *path, struct statfs *buf);
       int fstatfs(int fd, struct statfs *buf);


DESCRIPTION

       statfs  returns  information  about a mounted file system.
       path is the path name  of  any  file  within  the  mounted
       filesystem.   buf  is  a  pointer  to  a  statfs structure
       defined as follows:

              struct statfs {
                 long    f_type;     /* type of filesystem (see below) */
                 long    f_bsize;    /* optimal transfer block size */
                 long    f_blocks;   /* total data blocks in file system */
                 long    f_bfree;    /* free blocks in fs */
                 long    f_bavail;   /* free blocks avail to non-superuser */
                 long    f_files;    /* total file nodes in file system */
                 long    f_ffree;    /* free file nodes in fs */
                 fsid_t  f_fsid;     /* file system id */
                 long    f_namelen;  /* maximum length of filenames */
                 long    f_spare[6]; /* spare for later */
              };

              File system types:

              linux/affs_fs.h:
                 AFFS_SUPER_MAGIC      0xADFF
              linux/ext_fs.h:
                 EXT_SUPER_MAGIC       0x137D
              linux/ext2_fs.h:
                 EXT2_OLD_SUPER_MAGIC  0xEF51
                 EXT2_SUPER_MAGIC      0xEF53
              linux/hpfs_fs.h:
                 HPFS_SUPER_MAGIC      0xF995E849
              linux/iso_fs.h:
                 ISOFS_SUPER_MAGIC     0x9660
              linux/minix_fs.h:
                 MINIX_SUPER_MAGIC     0x137F /* orig. minix */
                 MINIX_SUPER_MAGIC2    0x138F /* 30 char minix */
                 MINIX2_SUPER_MAGIC    0x2468 /* minix V2 */
                 MINIX2_SUPER_MAGIC2   0x2478 /* minix V2, 30 char names */
              linux/msdos_fs.h:
                 MSDOS_SUPER_MAGIC     0x4d44
              linux/ncp_fs.h:
                 NCP_SUPER_MAGIC       0x564c
              linux/nfs_fs.h:
                 NFS_SUPER_MAGIC       0x6969
              linux/proc_fs.h:
                 SMB_SUPER_MAGIC       0x517B
              linux/sysv_fs.h:
                 XENIX_SUPER_MAGIC     0x012FF7B4
                 SYSV4_SUPER_MAGIC     0x012FF7B5
                 SYSV2_SUPER_MAGIC     0x012FF7B6
                 COH_SUPER_MAGIC       0x012FF7B7
              linux/ufs_fs.h:
                 UFS_MAGIC             0x00011954
              linux/xia_fs.h:
                 _XIAFS_SUPER_MAGIC    0x012FD16D

       Fields that are undefined for a particular file system are
       set  to  0.  fstatfs returns the same information about an
       open file referenced by descriptor fd.


RETURN VALUE

       On success, zero is returned.  On error, -1  is  returned,
       and errno is set appropriately.


ERRORS

       For statfs:

       ENOTDIR
              A  component  of  the  path prefix of path is not a
              directory.

       ENAMETOOLONG
              path is too long.

       ENOENT The file referred to by path does not exist.

       EACCES Search permission is denied for a component of  the
              path prefix of path.

       ELOOP  Too  many symbolic links were encountered in trans­
              lating path.

       EFAULT Buf or path points to an invalid address.

       EIO    An I/O error occurred while reading from or writing
              to the file system.

       ENOMEM Insufficient kernel memory was available.

       ENOSYS The  filesystem path is on does not support statfs.

       For fstatfs:

       EBADF  fd is not a valid open file descriptor.

       EFAULT buf points to an invalid address.


       ENOSYS The  filesystem  fd  is  open  on  does not support
              statfs.


CONFORMING TO

       The Linux statfs was inspired by the 4.4BSD one (but  they
       do not use the same structure).


SEE ALSO

       stat(2)