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preap(1)			  User Commands 			preap(1)

NAME
     preap - force a defunct process to be reaped by its parent

SYNOPSIS
     preap [-F] pid...

DESCRIPTION
     A defunct (or zombie) process is one whose exit status has yet to be reaped
     by  its  parent.  The exit status is reaped via the wait(3C), waitid(2), or
     waitpid(3C) system call. In the normal course of system operation,  zombies
     may occur, but are typically short-lived. This may happen if a parent exits
     without  having  reaped  the exit status of some or all of its children. In
     that case, those children are reparented to PID 1. See init(1M), which  pe-
     riodically reaps such processes.

     An  irresponsible parent process may not exit for a very long time and thus
     leave zombies on the system. Since the operating system destroys nearly all
     components of a process before it becomes defunct, such  defunct  processes
     do  not  normally impact system operation. However, they do consume a small
     amount of system memory.

     preap forces the parent of the process specified by pid to  waitid(3C)  for
     pid, if pid represents a defunct process.

     preap  will  attempt  to  prevent the administrator from unwisely reaping a
     child process which might soon be reaped by the parent, if:

       *  The process is a child of init(1M).

       *  The parent process is stopped and might wait on the child when  it  is
	  again allowed to run.

       *  The process has been defunct for less than one minute.

OPTIONS
     The following option is supported:

     -F       Forces the parent to reap the child, overriding safety checks.

OPERANDS
     The following operand is supported:

     pid      Process ID list.

EXIT STATUS
     The following exit values are returned by preap, which prints the exit sta-
     tus of each target process reaped:

     0	      Successfully operation.

     non-zero Failure,	such  as  no such process, permission denied, or invalid
	      option.

ATTRIBUTES
     See attributes(5) for descriptions of the following attributes:

     +------------------------------+-----------------------------+
     |	     ATTRIBUTE TYPE	    |	   ATTRIBUTE VALUE	  |
     +------------------------------+-----------------------------+
     | Availability		    |SUNWesu (32-bit)		  |
     +------------------------------+-----------------------------+
     |				    |SUNWesxu (64-bit)		  |
     +------------------------------+-----------------------------+

SEE ALSO
     proc(1), init(1M), waitid(2), wait(3C), waitpid(3C), proc(4), attributes(5)

WARNINGS
     preap should be applied sparingly and only in situations in which	the  ad-
     ministrator  or  developer has confirmed that defunct processes will not be
     reaped by the parent process. Otherwise, applying preap may damage the par-
     ent process in unpredictable ways.

SunOS 5.10			   26 Mar 2001				preap(1)

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