swapon(3) [netbsd man page]

SWAPON(3)						   BSD Library Functions Manual 						 SWAPON(3)

NAME

     swapon -- add a swap device for interleaved paging/swapping

SYNOPSIS

     #include <unistd.h>

     int
     swapon(const char *special);

DESCRIPTION

     This interface is provided for compatibility only and has been obsoleted by swapctl(2).

     swapon() makes the block device special available to the system for allocation for paging and swapping.  The names of potentially available
     devices are known to the system and defined at system configuration time.	The size of the swap area on special is calculated at the time the
     device is first made available for swapping.

RETURN VALUES

     If an error has occurred, a value of -1 is returned and errno is set to indicate the error.

ERRORS

     swapon() succeeds unless:

     [ENOTDIR]	   A component of the path prefix is not a directory.

     [ENAMETOOLONG]
		   A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} characters.

     [ENOENT]	   The named device does not exist.

     [EACCES]	   Search permission is denied for a component of the path prefix.

     [ELOOP]	   Too many symbolic links were encountered in translating the pathname.

     [EPERM]	   The caller is not the super-user.

     [ENOTBLK]	   special is not a block device.

     [EBUSY]	   The device specified by special has already been made available for swapping

     [EINVAL]	   The device configured by special was not configured into the system as a swap device.

     [ENXIO]	   The major device number of special is out of range (this indicates no device driver exists for the associated hardware).

     [EIO]	   An I/O error occurred while opening the swap device.

     [EFAULT]	   special points outside the process's allocated address space.

SEE ALSO

     swapctl(2), swapctl(8), swapon(8)

HISTORY

     The swapon() function call appeared in 4.0BSD and was removed NetBSD 1.3

BUGS

     This call will be upgraded in future versions of the system.

BSD
								   June 4, 1993 							       BSD

SWAPON(8)						     Linux Programmer's Manual							 SWAPON(8)

NAME

       swapon, swapoff - enable/disable devices and files for paging and swapping

SYNOPSIS

       /sbin/swapon [-h -V]
       /sbin/swapon -a [-v] [-e]
       /sbin/swapon [-v] [-p priority]	specialfile ...
       /sbin/swapon [-s]
       /sbin/swapoff [-h -V]
       /sbin/swapoff -a
       /sbin/swapoff specialfile ...

DESCRIPTION

       Swapon  is used to specify devices on which paging and swapping are to take place.  Calls to swapon normally occur in the system multi-user
       initialization file /etc/rc making all swap devices available, so that the paging and  swapping	activity  is  interleaved  across  several
       devices and files.

       Normally, the first form is used:

       -h     Provide help

       -V     Display version

       -s     Display swap usage summary by device. Equivalent to "cat /proc/swaps".  Not available before Linux 2.1.25.

       -a     All  devices marked as ``swap'' swap devices in /etc/fstab are made available. Devices that are already running as swap are silently
	      skipped.

       -e     When -a is used with swapon, -e makes swapon silently skip devices that do not exist.

       -p priority
	      Specify priority for swapon.  This option is only available if swapon was compiled under and is used under a 1.3.2 or later  kernel.
	      priority	is a value between 0 and 32767. See swapon(2) for a full description of swap priorities. Add pri=value to the option field
	      of /etc/fstab for use with swapon -a.

       Swapoff disables swapping on the specified devices and files.  When the -a flag is given, swapping is disabled on all  known  swap  devices
       and files (as found in /proc/swaps or /etc/fstab).

NOTE

       You should not use swapon on a file with holes.	Swap over NFS may not work.

SEE ALSO

       swapon(2), swapoff(2), fstab(5), init(8), mkswap(8), rc(8), mount(8)

FILES

       /dev/hd??  standard paging devices
       /dev/sd??  standard (SCSI) paging devices
       /etc/fstab ascii filesystem description table

HISTORY

       The swapon command appeared in 4.0BSD.

Linux 1.x							 25 September 1995							 SWAPON(8)