NAME    [Toc]    [Back]

       plock - Lock the text and/or data segments of a process in
       memory

SYNOPSIS    [Toc]    [Back]

       #include <sys/lock.h>

       int plock(
               int opr );

PARAMETERS    [Toc]    [Back]

       Specifies one of the following operations: Locks the  text
       and  data  segments  into  memory.  Locks the text segment
       into memory.  Locks the data segment into memory.  Removes
       locks.

DESCRIPTION    [Toc]    [Back]

       The  plock()  function  locks  or unlocks a process's text
       segments, data segments, or both in physical memory.  When
       locked,  the  physical  pages  containing the text or data
       segment will not be paged out.  It is an error to  lock  a
       segment that is already locked.

       The  caller  must  have  superuser  privilege  to  use the
       plock() function.

       Note that memory acquired subsequent to a plock() call may
       or  may not be locked in memory, depending on the specific
       acquisition method. Memory acquired by using the brk()  or
       sbrk()  function  will  be  locked if the data segment was
       locked. Memory acquired by means of the mmap() or vm_allocate()
 function will not be locked.

RETURN VALUES    [Toc]    [Back]

       Upon  successful  completion,  a  value  of  0  (zero)  is
       returned to the calling process. Otherwise, a value of  -1
       is returned and errno is set to indicate the error.

ERRORS    [Toc]    [Back]

       If  the plock() function fails, errno may be set to one of
       the following values: There are insufficient resources  to
       perform the operation.  One of the following occurred: The
       opr parameter is PROCLOCK, but the  text  segment  or  the
       data segment is already locked.  The opr parameter is TXTLOCK,
 but the text segment is  already  locked.   The  opr
       parameter  is  DATLOCK,  but  the  data segment is already
       locked.  The opr parameter is UNLOCK, but neither the text
       segment  nor  the data segment is locked.  The caller does
       not have appropriate privilege.

SEE ALSO    [Toc]    [Back]

       Functions: brk(2), mmap(2)



                                                         plock(2)