GETFSSTAT(2) BSD System Calls Manual GETFSSTAT(2)NAME
getfsstat, getvfsstat — get list of all mounted filesystems
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 flags);
getvfsstat(struct statfs *buf, struct statvfs *vbuf, long vbufsize,
int flags);
DESCRIPTIONGetfsstat() returns information about all mounted filesystems. Buf is a
pointer to statfs structures defined as follows:
typedef struct fsid { int32_t val[2]; } fsid_t; /* file system id type */
/*
* file system statistics
*/
#define MFSNAMELEN 16 /* length of fs type name, including null */
#define MNAMELEN 90 /* length of buffer for returned name */
struct statfs {
long f_spare2; /* placeholder */
long f_bsize; /* fundamental file system block size */
long f_iosize; /* optimal transfer block size */
long f_blocks; /* total data blocks in file system */
long f_bfree; /* free blocks in fs */
long f_bavail; /* free blocks avail to non-superuser */
long f_files; /* total file nodes in file system */
long f_ffree; /* free file nodes in fs */
fsid_t f_fsid; /* file system id */
uid_t f_owner; /* user that mounted the filesystem */
int f_type; /* type of filesystem (see below) */
int f_flags; /* copy of mount flags */
long f_spare[2]; /* spare for later */
char f_fstypename[MFSNAMELEN];/* fs type name */
char f_mntonname[MNAMELEN];/* directory on which mounted */
char f_mntfromname[MNAMELEN];/* mounted filesystem */
};
The flags that may be returned include:
MNT_RDONLY The filesystem is mounted read-only; Even the super-user
may not write on it.
MNT_NOEXEC Files may not be executed from the filesystem.
MNT_NOSUID Setuid and setgid bits on files are not honored when
they are executed.
MNT_NODEV Special files in the filesystem may not be opened.
MNT_SYNCHRONOUS All I/O to the filesystem is done synchronously.
MNT_ASYNC No filesystem I/O is done synchronously.
MNT_LOCAL The filesystem resides locally.
MNT_QUOTA The filesystem has quotas enabled on it.
MNT_ROOTFS Identifies the root filesystem.
MNT_EXRDONLY The filesystem is exported read-only.
MNT_EXPORTED The filesystem is exported for both reading and writing.
MNT_DEFEXPORTED The filesystem is exported for both reading and writing
to any Internet host.
MNT_EXPORTANON The filesystem maps all remote accesses to the anonymous
user.
MNT_EXKERB The filesystem is exported with Kerberos uid mapping.
Fields that are undefined for a particular filesystem are set to -1. The
buffer is filled with an array of fsstat structures, one for each mounted
filesystem up to the size specified by bufsize.
If buf is given as NULL, getfsstat() returns just the number of mounted
filesystems.
Normally flags should be specified as MNT_WAIT. If flags is set to
MNT_NOWAIT, getfsstat() will return the information it has available
without requesting an update from each filesystem. Thus, some of the
information will be out of date, but getfsstat() will not block waiting
for information from a filesystem that is unable to respond.
Getvfsstat() returns extended information about all mounted filesystems.
Note that vbufsize represents the size of vbuf, and buf is expected to be
of contemporary size for its own structures.
RETURN VALUES
Upon successful completion, the number of fsstat structures is returned.
Otherwise, -1 is returned and the global variable errno is set to indi‐
cate the error.
ERRORSGetfsstat() and getvfsstat() fail if one or more of the following are
true:
[EFAULT] Buf points to an invalid address.
[EIO] An I/O error occurred while reading from or writing to
the filesystem.
SEE ALSOstatfs(2), fstab(5), mount(8)HISTORY
The getfsstat() function first appeared in 4.4BSD.
BSD May 25, 1995 BSD
