osf1 man page for nsg_init

nsg_init(3)						     Library Functions Manual						       nsg_init(3)

NAME
       nsg_init - Look up or create a NUMA Scheduling Group (libnuma library)

SYNOPSIS
       #include <numa.h>

       nsgid_t nsg_init(
	       key_t key,
	       ulong_t flags );

PARAMETERS
       Specifies  the key that identifies the NUMA Scheduling Group (NSG). This value may be one of the following: An arbitrary binary value other
       than zero If the NSG_GETBYPID flag is set, the process ID of a member process of the requested NSG Specifies lookup or creation flags.  See
       DESCRIPTION for details.

DESCRIPTION
       The  nsg_init()	function  looks up and possibly creates the NSG identified by the key parameter.  The flags parameter supplies options for
       the lookup or create operation.

       If the flags parameter includes the NSG_GETBYPID flag, then the key parameter is the process ID (pid_t) of a process that  is  currently  a
       member  of  the	requested NSG. Otherwise, key is an arbitrary binary value that identifies the requested NSG. If the NSG identified by key
       does not already exist, an error will be returned unless the NSG_CREATE flag is specified.

       The NSG_CREATE flag instructs nsg_init() to create the NSG and return its identifier.  If NSG_CREATE and NSG_EXCL are  both  specified,	an
       error will be returned if the NSG identified by key already exists.

       If  the	NSG_GETBYPID  flag  is set and the process identified by the value of key does not exist, an error is returned.  If the NSG_CREATE
       flag is set along with the NSG_GETBYPID flag, and the process identified by the value of key exists but is not currently  a  member  of	an
       NSG,  a new NSG will be created using the value of key (the process's ID) and the process will be attached to the new NSG. This establishes
       the "home RAD" of the process as the home RAD for the NSG.

       After creating a new NSG, the nsg_init()  function  initializes	an  associated	nsgid_ds  structure  as  follows:  The	nsg_perm.cuid  and
       nsg_perm.uid  members  are  set	equal to the effective user ID of the calling process.	The nsg_perm.cgid and nsg_perm.gid members are set
       equal to the effective group ID of the calling process.	The low order nine bits of nsg_perm.mode are set equal to the low order nine  bits
       of flags.  The nsg_perm.nattach member is set to zero (or 1 if NSG_GETBYPID is specified in flags).

       The  nsg_perm.mode  permissions	control operations on NSGs as follows: Write permission is required to destroy the NSG or to set the owner
       IDs and permissions.  Read permission is required to query the NSG status or membership roster.	Execute permission is required	to  attach
       processes or threads to an NSG.

       If  NSG_CLEANUP	is  specified  in  flags, the NSG will be marked for automatic deletion when the nsg_perm.nattach member of the associated
       nsgid_ds structure transitions from non-zero to zero.

RETURN VALUES
       Success.  Failure. In this case, errno is set to indicate the error.

ERRORS
       If the nsg_init() function fails, it sets errno to one of the following values for the specified condition: An NSG already exists  for  the
       specified  key,	but  the caller does not have access based on the NSG's current permissions.  An NSG already exists for the specified key,
       but NSG_CREATE and NSG_EXCL flags were specified.  No NSG exists for the specified key, and the NSG_CREATE flag	was  not  specified.   The
       NSG_GETBYPID flag was set and the process identified by key was not found.  One or more illegal values for flags was set.

SEE ALSO
       Functions: nsg_attach_pid(3), nsg_attach_thread(3), numa_intro(3)

       Files: numa_types(4)

																       nsg_init(3)