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GETFSSTAT(2) FreeBSD System Calls Manual GETFSSTAT(2)
NAME
getfsstat - get list of all mounted file systems
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/param.h>
#include <sys/ucred.h>
#include <sys/mount.h>
int
getfsstat(struct statfs *buf, long bufsize, int mode);
DESCRIPTION
The getfsstat() system call returns information about all mounted file
systems. The buf argument is a pointer to 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 statfs structures, one for each
mounted file system up to the byte count specified by bufsize. Note, the
bufsize argument is the number of bytes that buf can hold, not the count
of statfs structures it will hold.
If buf is given as NULL, getfsstat() returns just the number of mounted
file systems.
Normally mode should be specified as MNT_WAIT. If mode is set to
MNT_NOWAIT, 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information will be out of date, but getfsstat() will not block waiting
for information from a file system that is unable to respond. It will
also skip any file system that is in the process of being unmounted, even
if the unmount would eventually fail.
RETURN VALUES
Upon successful completion, the number of statfs structures is returned.
Otherwise, -1 is returned and the global variable errno is set to
indicate the error.
ERRORS
The getfsstat() system call fails if one or more of the following are
true:
[EFAULT] The buf argument points to an invalid address.
[EINVAL] mode is set to a value other than MNT_WAIT or
MNT_NOWAIT.
[EIO] An I/O error occurred while reading from or writing to
the file system.
[EINTEGRITY] Corrupted data was detected while reading from the
file system.
SEE ALSO