STATFS(2)

NAME
statfs - get file system statistics

SYNOPSIS
#include <sys/vfs.h>

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

int fstatfs(fd, buf)
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:
    typedef struct {
    	long	val[2];
    } fsid_t;
    struct statfs {
    	long	f_type; 	/* type of info, zero for now */
    	long	f_bsize;	/* fundamental file system block size */
    	long	f_blocks;	/* total blocks in file system */
    	long	f_bfree;	/* free blocks */
    	long	f_bavail;	/* free blocks available to non-super-user */
    	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[7];	/* spare for later */
    };

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.

RETURN VALUE
Upon successful completion, a value of 0 is returned. Otherwise, -1 is returned and the global variable errno is set to indicate the error.

ERRORS
statfs() fails if one or more of the following are true:

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

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

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 translating 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.

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

EBADF
    fd is not a valid open file descriptor.

EFAULT
    buf points to an invalid address.

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