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@(#)getfsstat.2 6.3 (Berkeley) 03/06/90

C 7 getfsstat - get list of all mounted filesystems

#include <sys/types.h>
#include <sys/mount.h>

getfsstat(buf, bufsize, flags)
struct statfs *buf[];
long bufsize;
int flags;

Getfsstat returns information about all mounted filesystems. Buf is a pointer to an array of statfs structures defined as follows:

typedef quad fsid_t;
#define MNAMELEN 32 /* length of buffer for returned name */
struct statfs {
 short f_type; /* type of filesystem (see below) */
 short f_flags; /* copy of mount flags */
 long f_fsize; /* fundamental filesystem block size */
 long f_bsize; /* optimal transfer block size */
 long f_blocks; /* total data blocks in filesystem */
 long f_bfree; /* free blocks in fs */
 long f_bavail; /* free blocks avail to non-superuser */
 long f_files; /* total file nodes in filesystem */
 long f_ffree; /* free file nodes in fs */
 fsid_t f_fsid; /* filesystem id */
 long f_spare[6]; /* spare for later */
 char f_mntonname[MNAMELEN]; /* directory on which mounted */
 char f_mntfromname[MNAMELEN]; /* mounted filesystem */
};
/*
 * File system types.
 */
#define MOUNT_UFS 1
#define MOUNT_NFS 2
#define MOUNT_PC 3

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 zero, getfsstat returns just the number of mounted filesystems.

Normally flags should be specified as MNT_WAIT. If flags is set to MNT_NOWAIT, then 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 Thus, some of the information will be out of date, but getfsstat will not block waiting for information from a filesystem that is unable to respond.

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. Getfsstat fails if one or more of the following are true:

15 EFAULT Buf points to an invalid address.

15 EIO An I/O error occurred while reading from or writing to the filesystem.

statfs(2), fstab(5), mount(8)