---
name: "statvfs"
section: "3"
platform: "linux"
package: "man-pages"
version: "6.19-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "freebsd", "macos"]
url: "https://new.carta.tech/statvfs/3"
---

# statvfs(3)

get filesystem statistics

## NAME

statvfs, fstatvfs - get filesystem statistics

## LIBRARY

Standard C library (*libc*, *-lc*)

## SYNOPSIS

```
#include <sys/statvfs.h>
```

**int statvfs(const char \*restrict** *path***, struct statvfs \*restrict** *buf***);** **int fstatvfs(int** *fd***, struct statvfs \****buf***);**

## DESCRIPTION

The function **statvfs**() returns information about a mounted filesystem. *path* is the pathname of any file within the mounted filesystem. *buf* is a pointer to a *statvfs* structure defined approximately as follows:

```
struct statvfs {
    unsigned long  f_bsize;    /* Filesystem block size */
    unsigned long  f_frsize;   /* Fragment size */
    fsblkcnt_t     f_blocks;   /* Size of fs in f_frsize units */
    fsblkcnt_t     f_bfree;    /* Number of free blocks */
    fsblkcnt_t     f_bavail;   /* Number of free blocks for
                                  unprivileged users */
    fsfilcnt_t     f_files;    /* Number of inodes */
    fsfilcnt_t     f_ffree;    /* Number of free inodes */
    fsfilcnt_t     f_favail;   /* Number of free inodes for
                                  unprivileged users */
    unsigned long  f_fsid;     /* Filesystem ID */
    unsigned long  f_flag;     /* Mount flags */
    unsigned long  f_namemax;  /* Maximum filename length */
};
```

Here the types *fsblkcnt\_t* and *fsfilcnt\_t* are defined in *\<sys/types.h\>*. Both used to be *unsigned long*.

The field *f\_flag* is a bit mask indicating various options that were employed when mounting this filesystem. It contains zero or more of the following flags:

- **ST\_MANDLOCK**

  Mandatory locking is permitted on the filesystem (see [**fcntl**(2)](/fcntl/2.md)).

- **ST\_NOATIME**

  Do not update access times; see [**mount**(2)](/mount/2.md).

- **ST\_NODEV**

  Disallow access to device special files on this filesystem.

- **ST\_NODIRATIME**

  Do not update directory access times; see [**mount**(2)](/mount/2.md).

- **ST\_NOEXEC**

  Execution of programs is disallowed on this filesystem.

- **ST\_NOSUID**

  The set-user-ID and set-group-ID bits are ignored by [**exec**(3)](/exec/3.md) for executable files on this filesystem

- **ST\_RDONLY**

  This filesystem is mounted read-only.

- **ST\_RELATIME**

  Update atime relative to mtime/ctime; see [**mount**(2)](/mount/2.md).

- **ST\_SYNCHRONOUS**

  Writes are synched to the filesystem immediately (see the description of **O\_SYNC** in [**open**(2)](/open/2.md)).

It is unspecified whether all members of the returned struct have meaningful values on all filesystems.

**fstatvfs**() 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 to indicate the error.

## ERRORS

- **EACCES**

  (**statvfs**()) Search permission is denied for a component of the path prefix of *path*. (See also [**path\_resolution**(7)](/path_resolution/7.md).)

- **EBADF**

  (**fstatvfs**()) *fd* is not a valid open file descriptor.

- **EFAULT**

  *Buf* or *path* points to an invalid address.

- **EINTR**

  This call was interrupted by a signal; see [**signal**(7)](/signal/7.md).

- **EIO**

  An I/O error occurred while reading from the filesystem.

- **ELOOP**

  (**statvfs**()) Too many symbolic links were encountered in translating *path*.

- **ENAMETOOLONG**

  (**statvfs**()) *path* is too long.

- **ENOENT**

  (**statvfs**()) The file referred to by *path* does not exist.

- **ENOMEM**

  Insufficient kernel memory was available.

- **ENOSYS**

  The filesystem does not support this call.

- **ENOTDIR**

  (**statvfs**()) A component of the path prefix of *path* is not a directory.

- **EOVERFLOW**

  Some values were too large to be represented in the returned struct.

## ATTRIBUTES

For an explanation of the terms used in this section, see [**attributes**(7)](/attributes/7.md).

| | | |
| --- | --- | --- |
| **Interface** | **Attribute** | **Value** |
| **statvfs**(), **fstatvfs**() | Thread safety | MT-Safe |

## VERSIONS

Only the **ST\_NOSUID** and **ST\_RDONLY** flags of the *f\_flag* field are specified in POSIX.1. To obtain definitions of the remaining flags, one must define **\_GNU\_SOURCE**.

## NOTES

The Linux kernel has system calls [**statfs**(2)](/statfs/2.md) and [**fstatfs**(2)](/fstatfs/2.md) to support this library call.

The glibc implementations of

```
pathconf(path, _PC_REC_XFER_ALIGN);
pathconf(path, _PC_ALLOC_SIZE_MIN);
pathconf(path, _PC_REC_MIN_XFER_SIZE);
```

respectively use the *f\_frsize*, *f\_frsize*, and *f\_bsize* fields returned by a call to **statvfs**() with the argument *path*.

Under Linux, *f\_favail* is always the same as *f\_ffree*, and there's no way for a filesystem to report otherwise. This is not an issue, since no filesystems with an inode root reservation exist.

## STANDARDS

POSIX.1-2008.

## HISTORY

POSIX.1-2001.

Before glibc 2.13, **statvfs**() populated the bits of the *f\_flag* field by scanning the mount options shown in */proc/mounts*. However, starting with Linux 2.6.36, the underlying [**statfs**(2)](/statfs/2.md) system call provides the necessary information via the *f\_flags* field, and since glibc 2.13, the **statvfs**() function will use information from that field rather than scanning */proc/mounts*.

## SEE ALSO

[**statfs**(2)](/statfs/2.md)