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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 periodically 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:

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

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

         o  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
       status 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:


       tab()    allbox;    cw(2.750000i)|     cw(2.750000i)     lw(2.750000i)|
       lw(2.750000i).    ATTRIBUTE   TYPEATTRIBUTE  VALUE  AvailabilitySUNWesu
       (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
       administrator or developer has confirmed that  defunct  processes  will
       not be reaped by the parent process. Otherwise, applying preap may dam-
       age the parent process in unpredictable ways.



SunOS 5.10                        26 Mar 2001                         preap(1)