freebsd-nq/lib/libc/sys/getfsstat.2
1997-02-10 07:29:25 +00:00

163 lines
5.6 KiB
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.\" @(#)getfsstat.2 8.1 (Berkeley) 6/9/93
.\"
.Dd June 9, 1993
.Dt GETFSSTAT 2
.Os
.Sh NAME
.Nm getfsstat
.Nd get list of all mounted filesystems
.Sh SYNOPSIS
.Fd #include <sys/param.h>
.Fd #include <sys/ucred.h>
.Fd #include <sys/mount.h>
.Ft int
.Fn getfsstat "struct statfs *buf" "long bufsize" "int flags"
.Sh DESCRIPTION
.Fn Getfsstat
returns information about all mounted filesystems.
.Fa Buf
is a pointer to
.Xr statfs
structures defined as follows:
.Bd -literal
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 */
};
/*
* File system types.
*/
#define MOUNT_NONE 0
#define MOUNT_UFS 1 /* Fast Filesystem */
#define MOUNT_NFS 2 /* Sun-compatible Network Filesystem */
#define MOUNT_MFS 3 /* Memory-based Filesystem */
#define MOUNT_MSDOS 4 /* MS/DOS Filesystem */
#define MOUNT_LFS 5 /* Log-based Filesystem */
#define MOUNT_LOFS 6 /* Loopback Filesystem */
#define MOUNT_FDESC 7 /* File Descriptor Filesystem */
#define MOUNT_PORTAL 8 /* Portal Filesystem */
#define MOUNT_NULL 9 /* Minimal Filesystem Layer */
#define MOUNT_UMAP 10 /* User/Group Identifier Remapping Filesystem */
#define MOUNT_KERNFS 11 /* Kernel Information Filesystem */
#define MOUNT_PROCFS 12 /* /proc Filesystem */
#define MOUNT_AFS 13 /* Andrew Filesystem */
#define MOUNT_CD9660 14 /* ISO9660 (aka CDROM) Filesystem */
#define MOUNT_UNION 15 /* Union (translucent) Filesystem */
#define MOUNT_DEVFS 16 /* existing device Filesystem */
#define MOUNT_EXT2FS 17 /* Linux EXT2FS */
#define MOUNT_TFS 18 /* Netcon Novell filesystem */
#define MOUNT_MAXTYPE 18
.Ed
.Pp
Fields that are undefined for a particular filesystem are set to -1.
The buffer is filled with an array of
.Fa fsstat
structures, one for each mounted filesystem
up to the size specified by
.Fa bufsize .
.Pp
If
.Fa buf
is given as NULL,
.Fn getfsstat
returns just the number of mounted filesystems.
.Pp
Normally
.Fa flags
should be specified as
.Dv MNT_WAIT .
If
.Fa flags
is set to
.Dv MNT_NOWAIT ,
.Fn 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
.Fn getfsstat
will not block waiting for information from a filesystem that is
unable to respond.
.Sh RETURN VALUES
Upon successful completion, the number of
.Fa fsstat
structures is returned.
Otherwise, -1 is returned and the global variable
.Va errno
is set to indicate the error.
.Sh ERRORS
.Fn Getfsstat
fails if one or more of the following are true:
.Bl -tag -width Er
.It EFAULT
.Fa Buf
points to an invalid address.
.It EIO
An
.Tn I/O
error occurred while reading from or writing to the filesystem.
.El
.Sh SEE ALSO
.Xr statfs 2 ,
.Xr fstab 5 ,
.Xr mount 8
.Sh HISTORY
The
.Fn getfsstat
function first appeared in
.Bx 4.4 .