NAME
getfsstat
,
getvfsstat
—
get list of all mounted
filesystems
LIBRARY
library “libc”
SYNOPSIS
#include
<sys/param.h>
#include <sys/ucred.h>
#include <sys/mount.h>
int
getfsstat
(struct
statfs *buf, long
bufsize, int
flags);
#include
<sys/statvfs.h>
int
getvfsstat
(struct
statfs *buf, struct
statvfs *vbuf, long
vbufsize, int
flags);
DESCRIPTION
Getfsstat
()
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 80 /* 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_syncwrites; /* count of sync writes since mount */ long f_asyncwrites; /* count of async writes since mount */ char f_fstypename[MFSNAMELEN];/* fs type name */ char f_mntonname[MNAMELEN];/* directory on which mounted */ long f_syncreads; /* count of sync reads since mount */ long f_asyncreads; /* count of async reads since mount */ short f_spares1; /* unused spare */ char f_mntfromname[MNAMELEN];/* mounted filesystem */ short f_spares2; /* unused spare */ long f_spare[2]; /* unused spare */ };
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 indicate the error.
ERRORS
Getfsstat
() 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 ALSO
HISTORY
The getfsstat
() function first appeared in
4.4BSD.