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dlm_glc_create(3)
NAME
  dlm_glc_create - Creates a group lock container

LIBRARY
  Distributed Lock Manager Library (libdlm.a)

SYNOPSIS
  #include <sys/dlm.h>

  dlm_status_t dlm_glc_create (
	   dlm_glc_id_t *idp,
	   dlm_glc_flags_t flags,
	   dlm_nsp_t *ns_listp,
	   int ns_num );

PARAMETERS
  idp	    Specifies a pointer to a location to which dlm_glc_create returns
	    a handle for the created group lock container. The returned group
	    lock container ID is valid only on the local cluster member.

  flags	    When provided, specifies flags that modify the operation. The
	    flags parameter is a bit mask that is the logical OR of each bit
	    set, where each bit corresponds to an option.

	    The dlm_glc_flags structure defines a symbolic name for each flag
	    bit. The following list describes each flag:

	    DLM_GLC_OWNED
		      Causes the distributed lock manager (DLM) to destroy
		      the group lock container, all group locks in it, and
		      all processes attached to it when the process that
		      created the container exits.

	    DLM_GLC_PERM
		      Marks the group lock container as permanent. It will
		      persist even after the last associated process detaches
		      from it. The DLM_GLC_PERM and DLM_GLC_OWNED flags are
		      mutually exclusive.

  ns_listp  Specifies a pointer to an array of namespace IDs. The
	    dlm_glc_create function assumes that the valid namespace IDs in
	    the array begin at the first element and are contiguous.

  ns_num    Specifies the number of elements (up to DLM_NSPROCMAX) in the
	    ns_listp array.

DESCRIPTION
  The dlm_glc_create() function creates a group lock container and attaches
  the calling process to it. Because the group lock container is attached to
  all namespaces specified by the ns_listp parameter, its caller must have
  previously attached to those namespaces.  Any namespaces the calling
  process joins after creating the group lock container do not become part of
  the existing container's namespace. Use the dlm_locktp() or dlm_quelocktp()
  function with the DLM_GROUP_LOCK flag to create new group locks in the
  container.

  By default, the container exists as long as at least one process is
  attached to it.  You can change this behavior by specifying either the
  DLM_GLC_OWNED or DLM_GLC_PERM flag.

  When a process attaches to a group lock container, it becomes a member of
  the process lock group and obtains the right to manipulate any lock
  associated with that container.  A group lock can be manipulated by only
  one group member at a time, although one member can cancel or dequeue
  another member's request for group locks in that container. A process can
  attach to only one group lock container at a time.

RETURN VALUES
  Upon completion, the dlm_glc_create() function call returns one of the
  following values:

  DLM_SUCCESS
	    The operation was completed successfully.

  DLM_ATTACHED
	    The process is already attached to a group lock container.

  DLM_BADPARAM
	    Illegal flags were supplied, an illegal namespace ID was provided
	    in the ns_listp parameter, or both DLM_GLC_OWNED and DLM_GLC_PERM
	    were specified.

  DLM_EFAULT
	    The DLM could not copy the namespace list or the group ID.

  DLM_ENOSYS
	    The DLM is not enabled.

  DLM_INSFMEM
	    Insufficient resources were available to perform the requested
	    operation.

  DLM_NOTATTACHED
	    The process is not attached to the DLM or to one of the specified
	    namespaces.

FILES
  /usr/include/sys/dlm.h
	    DLM library header file.

  /usr/examples/cluster/api_ex_master.c|api_ex_client.c
	    Source files for an example showing lock conversion and value
	    block usage.

RELATED INFORMATION
  Functions: dlm_cancel(3), dlm_cvt(3), dlm_detach(3), dlm_get_lkinfo(3),
  dlm_get_rsbinfo(3), dlm_glc_attach(3), dlm_glc_detach(3),
  dlm_glc_destroy(3), dlm_lock(3), dlm_notify(3), dlm_nsjoin(3),
  dlm_nsleave(3), dlm_perrno(3), dlm_quecvt(3), dlm_quelock(3),
  dlm_rd_attach(3), dlm_rd_collect(3), dlm_rd_detach(3), dlm_rd_validate(3),
  dlm_set_signal(3), dlm_unlock(3)

  File: dlm(4)

  TruCluster Server Cluster Highly Available Applications

Index for Section 3

Alphabetical listing for D

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