GETFSSTAT(2)              OpenBSD Programmer's Manual             GETFSSTAT(2)

NAME
     getfsstat - get list of all mounted file systems



SYNOPSIS
     #include <sys/param.h>
     #include <sys/mount.h>

     int
     getfsstat(struct statfs *buf, size_t bufsize, int flags);

DESCRIPTION
     getfsstat() returns information about all mounted file systems.  buf is a
     pointer to an array of statfs(2) structures defined as follows:

     typedef struct { int32_t val[2]; } fsid_t;

     #define MFSNAMELEN   16 /* length of fs type name, including NUL */
     #define MNAMELEN     32 /* length of buffer for returned name */

     struct statfs {
         u_int32_t  f_flags;       /* copy of mount flags */
         u_int32_t  f_bsize;       /* fundamental file system block size */
         u_int32_t  f_iosize;      /* optimal transfer block size */
         u_int32_t  f_blocks;      /* total data blocks in file system */
         u_int32_t  f_bfree;       /* free blocks in fs */
         u_int32_t  f_bavail;      /* free blocks avail to non-superuser */
         u_int32_t  f_files;       /* total file nodes in file system */
         u_int32_t  f_ffree;       /* free file nodes in fs */
         fsid_t     f_fsid;        /* file system id */
         uid_t      f_owner;       /* user that mounted the file system */
         u_int32_t  f_syncwrites;  /* count of sync writes since mount */
         u_int32_t  f_asyncwrites; /* count of async writes since mount */
         u_int32_t  f_spare[4];    /* spare for later */
         char       f_fstypename[MFSNAMELEN]; /* fs type name */
         char       f_mntonname[MNAMELEN];    /* directory on which mounted */
         char       f_mntfromname[MNAMELEN];  /* mounted file system */
         union mount_info mount_info;         /* per-filesystem mount options */
     };

     The buffer is filled with an array of statfs structures, one for each
     mounted file system up to the size specified by bufsize.

     If buf is NULL, getfsstat() returns just the number of mounted file sys-
     tems.

     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 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     information will be out of date, but getfsstat() will not block waiting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.

RETURN VALUES
     Upon successful completion, the number of statfs structures is returned.
     Otherwise, -1 is returned and the global variable errno is set to indi-
     cate the error.

ERRORS
     getfsstat() fails 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
                   file system.

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

HISTORY
     The getfsstat() function first appeared in 4.4BSD.

OpenBSD 2.6                      June 9, 1993                                2