---
name: "getvfsbyname"
section: "3"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd", "macos"]
url: "https://new.carta.tech/getvfsbyname"
---

# getvfsbyname(3)

get information about a file system

## NAME

**getvfsbyname** – get information about a file system

## LIBRARY

Standard C Library (libc, -lc)

## SYNOPSIS

**#include \<sys/param.h\>**

**#include \<sys/mount.h\>**

*int*\

**getvfsbyname**(*const char \*name*, *struct xvfsconf \*vfc*);

## DESCRIPTION

The **getvfsbyname**() function provides access to information about a file system module that is configured in the kernel. If successful, the requested file system *xvfsconf* is returned in the location pointed to by *vfc*. The fields in a “struct xvfsconf” are defined as follows:

- vfc\_name

  the name of the file system

- vfc\_typenum

  the file system type number assigned by the kernel

- vfc\_refcount

  the number of active mount points using the file system

- vfc\_flags

  flag bits, as described below

The flags are defined as follows:

- VFCF\_STATIC

  statically compiled into kernel

- VFCF\_NETWORK

  may get data over the network

- VFCF\_READONLY

  writes are not implemented

- VFCF\_SYNTHETIC

  data does not represent real files

- VFCF\_LOOPBACK

  aliases some other mounted FS

- VFCF\_UNICODE

  stores file names as Unicode

- VFCF\_JAIL

  can be mounted from within a jail if *allow.mount* and *allow.mount.\<vfc\_name\>* jail parameters are set

- VFCF\_DELEGADMIN

  supports delegated administration if *vfs.usermount* sysctl is set to 1

## RETURN VALUES

The **getvfsbyname()** function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

## ERRORS

The following errors may be reported:

- \[ENOENT\]

  The *name* argument specifies a file system that is unknown or not configured in the kernel.

## SEE ALSO

[lsvfs(1)](/lsvfs/1.md), [jail(2)](/jail/2.md), [mount(2)](/mount/2.md), [sysctl(3)](/sysctl/3.md), [jail(8)](/jail/8.md), [mount(8)](/mount/8.md), [sysctl(8)](/sysctl/8.md)

## HISTORY

A variant of the **getvfsbyname**() function first appeared in FreeBSD 2.0.