OpenVMS Alpha Galaxy Guide
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  13.1  SYS$CREATE_GALAXY_LOCK_TABLE

  This service allocates a galaxy locktable structure.  This
  structure is used to maintain information about the shared
  memory section, which this service also creates.  The first
  caller of the service with a unique locktable name creates the
  section.  Additional callers map it.  This shared memory sec-
  tion contains a set of galaxy locks.  All locks residing in the
  section are of the same size.  Once the locktable is created,
  the SYS$CREATE_GALAXY_LOCK service can be used to
  create and allocate a lock from the table.

  The flags GLCKTBL$C_PROCESS and GLCKTBL$C_

  SYSTEM specify whether the shared memory region is
  mapped into system space or process space.  Creation of
  process space sections requires the SHMEM privilege.
  Creation of system space sections requires the SHMEM
  and CMKRNL privileges.

  sys$create_galaxy_lock_table(name, accmode, section_size,
  section_type, prot, lock_size, handle)

                 size
  parameter      (bytes)      type                   usage

  name           8            input by value         address of
                                                     the lock table
                                                     name (ASCIZ)

  accmode        4            input by value         access mode of
                                                     the lock table
  section size      8         input by value         virtual size of
                                                     lock section
  section type      4         input by value         glcktbl$c_
                                                     process or
                                                     glcktbl$c_
                                                     system
  prot           4            input by value         protection ap-
                                                     plied to lock
                                                     section
  lock_size        4          input by value         size of the
                                                     galaxy locks in
                                                     the section
  handle         8            output by ref          lock table
                                                     handle

  Return status:

      SS$_ACCVIO
      SS$_BADPARAM
      SS$_CREATED

      SS$_IVLOCKID
      SS$_NOPRIV
      SS$_NOSHMEM

      SS$_NORMAL
      Any status from the shared memory support routines
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