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
Check Out this Related Man Page
swapon(2) System Calls Manual swapon(2) NAME
swapon - Adds a swap device for interleaved paging and swapping SYNOPSIS
swapon( char *path, int flags, int lowat, int hiwat ); PARAMETERS
Specifies the block special device to be made available. Specifies a flag. Only the MS_PREFER flag is currently supported, and it causes the specified path to be the preferred paging device. (Ignored on Tru64 UNIX.) Specifies the low water mark. (Ignored on Tru64 UNIX.) Specifies the high water mark. (Ignored on Tru64 UNIX.) DESCRIPTION
The swapon() function makes a block special device available to the system for allocation of paging and swapping space. (The operating system does not currently support paging and swapping to a normal file. All swapping and pages areas must be block special devices.) The calling process must have superuser privilege to call the swapon() function. RETURN VALUES
Upon successful completion, the swapon() function returns a value of 0 (zero). If an error has occurred, -1 is returned and errno is set to indicate the error. ERRORS
If the swapon() function fails, errno may be set to one of the following values: A component of the path prefix is not a directory. The pathname contains a character with the high-order bit set, the device was not specified, the device configured by the path parameter was not configured into the system as a swap device, or the device does not allow paging. A component of a pathname exceeded NAME_MAX charac- ters, or an entire pathname exceeded PATH_MAX characters. The named device does not exist. Search permission is denied for a component of the path prefix. Too many symbolic links were encountered in translating the pathname. The caller does not have appropriate privilege. The device specified by the path parameter has already been made available for swapping. The major device number of the path parameter is out of range (this indicates no device driver exists for the associated hardware). An I/O error occurred while opening the swap device. The path parameter points outside the process' allocated address space. An attempt was made to activate a paging file on a read-only file system. RELATED INFORMATION
Commands: swapon(8), config(8) delim off swapon(2)