.TH MOUNT 2
.UC 4
.SH NAME
mount, umount  \- mount and unmount filesystems.
.SH SYNOPSIS
.nf
.B #incldue <unistd.h> 
.B int mount (const char *devname, const char *dirname, int rw_flag);
.B int umount (const char *devname);
.fi
.SH DESCRIPTION
.B mount()
mounts the filesystem on the block device named 
.I *devname
onto the directory
.I dirname
.PP
.B umount()
unmounts the specified block device.
.PP
0 is returned on success, a negative value on error.
.SH ERRORS
.B -EBUSY
is returned under the following conditions:
.br
.IP 1.
There is activity in the directory you are trying to mount on
.IP 2.
You are attempting to mount on /.
.IP 3.
There is file system activity during umount, which could be as simple as a 
process having a directory under the mount point as wd. 
.PP
.B  -ENOENT
is returned if the block device or directory does not exist.
.PP
.B -ENOTBLK
is returned if you attempt to unmount a non-block device.
.PP
.B -EPERM
is returned under the following conditions:
.br
.IP 1.
You attempt to mount a non-block device.
.IP 2.
You attempt to mount on a non-directory.
.IP 3.
The filesystem is already mounted.
.SH FILES
linux/fs/super.c
.br
/usr/include/linux/sys.h
.br
/usr/include/unistd.h
.SH BUGS
.I rw_flag
is ignored.
.PP
non-super users may make    
.B mount() 
and
.B umount()
calls.
.PP
It is impossible to mount over root, as with BSD.
This can be considered a feature or misfeature 
depending on you you look at it -
as root will always be busy and probably shouldn't be mounted 
over.
.PP 
.B EBUSY, ENOTBLK, 
and 
.B EPERM
may be confused in some places.