mount(2)                                                           mount(2)

NAME
     mount - mount a file system

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

     int mount(const char *spec, const char *dir, int mflag,
            .../* int fstyp, const char *dataptr, sizet datalen */);

DESCRIPTION
     mount() mounts a removable file system contained in the block special
     file identified by spec in the directory identified by dir. spec and
     dir are pointers to pathnames. The argument fstyp is interpreted by
     mount() when either MSFSS or MSDATA is set in mflag. fstyp is the
     file system type number or a pointer to a string containing the file
     system type. The sysfs(2) system call can be used to determine the
     file system type number. If neither MSDATA or MSFSS is set in mflag,
     mount() defaults to the root file system type.

     If the MSDATA flag is set in mflag the system expects the dataptr and
     datalen arguments to be present. Together they describe a block of
     file-system specific data at address dataptr of length datalen. This
     is interpreted by file-system specific code within the operating sys-
     tem and its format depends on the file system type. If a particular
     file system type does not require this data, dataptr and datalen
     should both be zero. If the file system is to be mounted as read-only,
     MSRDONLY must be set in mflag.

     After a successful call to mount(), the name in dir refers to the root
     directory on the newly mounted file system.

     mount() may be invoked only by the superuser. The interface is
     intended for use only by the mount(1M) utility.

     mount() fails if one or more of the following apply:

     EBUSY         dir is currently mounted on, is someone's current work-
                   ing directory, or is otherwise busy.

     EBUSY         The special file associated with spec is currently
                   mounted.

     EBUSY         There are no more mount table entries.

     EFAULT        spec, dir, or datalen points outside the allocated
                   address space of the process.

     EINVAL        The super block has an invalid magic number or the fstyp
                   is invalid.





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mount(2)                                                           mount(2)

     ELOOP         Too many symbolic links were encountered in compiling
                   dir.

     ENAMETOOLONG  The length of the dir argument exceeds PATHMAX or
                   NAMEMAX.

     ENOENT        One of the named files does not exist.

     ENOTDIR       A component of a path prefix is not a directory.

     EPERM         The effective user ID is not superuser.

     EREMOTE       spec is remote and cannot be mounted.

     ENOLINK       dir points to a remote machine and the link to that
                   machine is no longer active.

     EMULTIHOP     Components of dir require hopping to multiple remote
                   machines.

     ENOTBLK       spec is not a block special file.

     ENXIO         The special file associated with spec does not exist.

     ENOTDIR       dir is not a directory.

     EROFS         spec is write protected and mflag requests write permis-
                   sion.

     ENOSPC        The file system state in the super-block is not FsOKAY
                   and mflag requests write permission.

RESULT
     Upon successful completion a value of 0 is returned. Otherwise, a
     value of -1 is returned and errno is set to indicate the error.

SEE ALSO
     mount(1M), sysfs(2), umount(2), fs(4).
















Page 2                       Reliant UNIX 5.44                Printed 11/98