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 requests that a removable file system contained on the block
special file identified by spec be mounted on the directory
identified by dir. spec and dir are pointers to path names. fstyp
is the file system type number. The sysfs(2) system call can be used
to determine the file system type number. If both the MSDATA and
MSFSS flag bits of mflag are off, the file system type defaults to
the root file system type. Only if either flag is on is fstyp used
to indicate the 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
system 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. Note that MSFSS is obsolete and is
ignored if MSDATA is also set, but if MSFSS is set and MSDATA is
not, dataptr and datalen are both assumed to be zero.
After a successful call to mount, all references to the file dir
refer to the root directory on the mounted file system.
The low-order bit of mflag is used to control write permission on the
mounted file system: if 1, writing is forbidden; otherwise writing
is permitted according to individual file accessibility.
mount may be invoked only by the super-user. It is intended for use
only by the mount utility.
mount fails if one or more of the following are true:
EBUSY dir is currently mounted on, is someone's current
working directory, or is otherwise busy.
EBUSY The device associated with spec is currently
mounted.
EBUSY There are no more mount table entries.
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mount(2) mount(2)
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.
ELOOP Too many symbolic links were encountered in
translating spec or dir.
ENAMETOOLONG The length of the path argument exceeds
{PATHMAX}, or the length of a path component
exceeds {NAMEMAX} while POSIXNOTRUNC is in
effect.
ENOENT None of the named files exists or is a null
pathname.
ENOTDIR A component of a path prefix is not a directory.
EPERM The effective user ID is not super-user.
EREMOTE spec is remote and cannot be mounted.
ENOLINK path points to a remote machine and the link to
that machine is no longer active.
EMULTIHOP Components of path require hopping to multiple
remote machines and the file system type does not
allow it.
ENOTBLK spec is not a block special device.
ENXIO The device associated with spec does not exist.
ENOTDIR dir is not a directory.
EROFS spec is write protected and mflag requests write
permission.
ENOSPC The file system state in the super-block is not
FsOKAY and mflag requests write permission.
SEE ALSO
sysfs(2), umount(2).
mount(1M), fs(4) in the System Administrator's Reference Manual.
DIAGNOSTICS
Upon successful completion a value of 0 is returned. Otherwise, a
value of -1 is returned and errno is set to indicate the error.
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