SPDX-License-Identifier: CC-BY-SA-4.0 OR BSD-2-Clause
brief: |
  Creates a port.
copyrights:
- Copyright (C) 2021 embedded brains GmbH (http://www.embedded-brains.de)
- Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR)
definition:
  default:
    attributes: null
    body: null
    params:
    - ${../../type/if/name:/name} ${.:/params[0]/name}
    - void *${.:/params[1]/name}
    - void *${.:/params[2]/name}
    - ${/c/if/uint32_t:/name} ${.:/params[3]/name}
    - ${../../type/if/id:/name} *${.:/params[4]/name}
    return: ${../../status/if/code:/name}
  variants: []
description: |
  This directive creates a port which resides on the local node.  The port has
  the user-defined object name specified in ${.:/params[0]/name}.  The assigned
  object identifier is returned in ${.:/params[4]/name}.  This identifier is
  used to access the port with other dual-ported memory port related
  directives.
enabled-by: true
index-entries:
- create a port
interface-type: function
links:
- role: interface-placement
  uid: header
- role: interface-ingroup
  uid: group
- role: constraint
  uid: /constraint/directive-ctx-devinit
- role: constraint
  uid: /constraint/directive-ctx-task
- role: constraint
  uid: /constraint/object-allocator
- role: constraint
  uid: ../constraint/max
- role: constraint
  uid: /constraint/obj-unlimited-alloc
name: rtems_port_create
notes: |
  The ${.:/params[1]/name} and ${.:/params[2]/name} parameters must be on a
  boundary defined by the target processor architecture.

  For control and maintenance of the port, RTEMS allocates a
  ${/glossary/dpcb:/term} from the local DPCB free pool and initializes it.
params:
- description: |
    is the object name of the port.
  dir: null
  name: name
- description: |
    is the internal start address of the memory area.
  dir: null
  name: internal_start
- description: |
    is the external start address of the memory area.
  dir: null
  name: external_start
- description: |
    is the length in bytes of the memory area.
  dir: null
  name: length
- description: |
    is the pointer to an object identifier variable.  The identifier of the
    created port will be stored in this variable, in case of a successful
    operation.
  dir: out
  name: id
return:
  return: null
  return-values:
  - description: |
      The requested operation was successful.
    value: ${../../status/if/successful:/name}
  - description: |
      The ${.:/params[0]/name} parameter was invalid.
    value: ${../../status/if/invalid-name:/name}
  - description: |
      The ${.:/params[3]/name} parameter was ${/c/if/null:/name}.
    value: ${../../status/if/invalid-address:/name}
  - description: |
      The ${.:/params[1]/name} parameter was not properly aligned.
    value: ${../../status/if/invalid-address:/name}
  - description: |
      The ${.:/params[2]/name} parameter was not properly aligned.
    value: ${../../status/if/invalid-address:/name}
  - description: |
      There was no inactive object available to create a port.  The number of
      port available to the application is configured through the
      ${/acfg/if/max-ports:/name} application configuration option.
    value: ${../../status/if/too-many:/name}
type: interface