getfsstat(2) get list of all mounted file systems

LIBRARY

Lb libc

SYNOPSIS

In sys/param.h In sys/ucred.h In sys/mount.h Ft int Fn getfsstat struct statfs *buf long bufsize int flags

DESCRIPTION

The Fn getfsstat system call returns information about all mounted file systems. The Fa buf argument is a pointer to Vt statfs structures, as described in statfs(2).

Fields that are undefined for a particular file system are set to -1. The buffer is filled with an array of Fa statfs structures, one for each mounted file system up to the byte count specified by Fa bufsize . Note, the Fa bufsize argument is the number of bytes that Fa buf can hold, not the count of statfs structures it will hold.

If Fa buf is given as NULL, Fn getfsstat returns just the number of mounted file systems.

Normally Fa flags should be specified as MNT_WAIT If Fa flags is set to MNT_NOWAIT Fn getfsstat will return the information it has available without requesting an update from each file system. Thus, some of the information will be out of date, but Fn getfsstat will not block waiting for information from a file system that is unable to respond.

RETURN VALUES

Upon successful completion, the number of Fa statfs structures is returned. Otherwise, -1 is returned and the global variable errno is set to indicate the error.

ERRORS

The Fn getfsstat system call fails if one or more of the following are true:

Bq Er EFAULT
The Fa buf argument points to an invalid address.
Bq Er EIO
An I/O error occurred while reading from or writing to the file system.

HISTORY

The Fn getfsstat system call first appeared in BSD 4.4