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 mlockall(2)							 mlockall(2)




 NAME
      mlockall() - lock a process virtual address space in memory

 SYNOPSIS
      #include <&lt&lt&lt;sys/mman.h>&gt&gt&gt;

      int mlockall( constant int flags);

 DESCRIPTION
      The mlockall() system call allows the calling process to lock its
      entire virtual address space into memory, making it immune to all
      routine swapping.

      flags may be one or both of the following:

	   MCL_CURRENT	       Lock the current process virtual address
			       space.  All addressable pages of the address
			       space are locked.

	   MCL_FUTURE	       Lock any future additions to the process
			       virtual address space.

      Note that MCL_FUTURE does not imply MCL_CURRENT.

      munlockall() or munlock() can be used to unlock all or a portion of
      the address space locked with mlockall().	 A single call to
      munlockall() removes all locks from the process virtual address space.
      An munlock() call results in only the specified pages being unlocked.

      Regardless of how many times a process locks a page, a single
      munlock() or munlockall() will unlock it.

      When memory is shared by multiple processes and mlocks are applied to
      the same physical page by multiple processes, a page remains locked
      until the last lock is removed from that page.

      Locks and MCL_FUTURE applied with mlockall() are not inherited by a
      child process.

      The effective user ID of the calling process must be a superuser or
      the user must be a member of a group that has the MLOCK privilege (see
      getprivgrp(2) and setprivgrp(1M)).

      Although plock() and the mlock() family of functions may be used
      together in an application, each may affect the other in unexpected
      ways.  This practice is not recommended.

 RETURN VALUE
      mlockall() returns the following values:





 Hewlett-Packard Company	    - 1 -   HP-UX Release 11i: November 2000






 mlockall(2)							 mlockall(2)




	    0	Successful completion.
	   -1	Failure.  The requested operation is not performed.  errno
		is set to indicate the error.

 ERRORS
      If mlockall() fails, errno is set to one of the following values:

	   [EINVAL]	  The flags field did not contain either MCL_CURRENT
			  and/or MCL_FUTURE.

	   [EAGAIN]	  There is not enough lockable memory in the system
			  to satisfy the locking request.

	   [EPERM]	  The effective user ID of the calling process is
			  not a superuser and the user does not belong to a
			  group that has the MLOCK privilege.

 EXAMPLES
      The following call to mlockall() locks the entire process virtual
      address space in memory and ensures that any future additions to the
      address space will also be locked in memory:

	   mlockall( (MCL_CURRENT | MCL_FUTURE) );

 SEE ALSO
      setprivgrp(1M), getprivgrp(2), mlock(2), munlock(2), munlockall(2),
      plock(2).

 STANDARDS CONFORMANCE
      mlockall(): POSIX Realtime Extensions, IEEE Std 1003.1b
























 Hewlett-Packard Company	    - 2 -   HP-UX Release 11i: November 2000