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@(#)statfs.2 6.2 (Berkeley) 11/24/89

C 7 statfs - get file system statistics

#include <sys/types.h>
#include <sys/mount.h>

statfs(path, buf)
char *path;
struct statfs *buf;

fstatfs(fd, buf)
int fd;
struct statfs *buf;

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:

typedef quad fsid_t;
#define MNAMELEN 32 /* length of buffer for returned name */
struct statfs {
 short f_type; /* type of filesystem (see below) */
 short f_flags; /* copy of mount flags */
 long f_fsize; /* fundamental file system block size */
 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_spare[6]; /* spare for later */
 char f_mntonname[MNAMELEN]; /* directory on which mounted */
 char f_mntfromname[MNAMELEN]; /* mounted filesystem */
};
/*
 * File system types.
 */
#define MOUNT_UFS 1
#define MOUNT_NFS 2
#define MOUNT_MFS 3
#define MOUNT_PC 4

Fields that are undefined for a particular file system are set to -1. Fstatfs returns the same information about an open file referenced by descriptor fd .

Upon successful completion, a value of 0 is returned. Otherwise, -1 is returned and the global variable errno is set to indicate the error. Statfs fails if one or more of the following are true:

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

15 EINVAL path contains a character with the high-order bit set.

15 ENAMETOOLONG The length of a component of path exceeds 255 characters, or the length of path exceeds 1023 characters.

15 ENOENT The file referred to by path does not exist.

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

15 ELOOP Too many symbolic links were encountered in translating path .

15 EFAULT Buf or path points to an invalid address.

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

Fstatfs fails if one or both of the following are true:

15 EBADF fd is not a valid open file descriptor.

15 EFAULT buf points to an invalid address.

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