EXIT(2) EXIT(2)
NAME
exit, _exit - terminate process
SYNOPSIS
void exit (status)
int status;
void exit (status)
int status;
DESCRIPTION
exit terminates the calling process with the following
consequences:
All of the file descriptors open in the calling process are
closed.
If the parent process of the calling process is executing a
wait, it is notified of the calling process's termination
and the low order eight bits (i.e., bits 0377) of status are
made available to it [see wait(2),waitpic(2)].
If the parent process of the calling process is not
executing a wait, the calling process is transformed into a
zombie process. A zombie process is a process that only
occupies a slot in the process table. It has no other space
allocated either in user or kernel space. The process table
slot that it occupies is partially overlaid with time
accounting information (see <sys/proc.h>) to be used by
times.
The parent process ID of all of the calling processes'
existing child processes and zombie processes is set to 1.
This means the initialization process [see intro(2)]
inherits each of these processes.
Each attached shared memory segment is detached and the
value of shmnattach in the data structure associated with
its shared memory identifier is decremented by 1.
For each semaphore for which the calling process has set a
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EXIT(2) EXIT(2)
semadj value [see semop(2)], that semadj value is added to
the semval of the specified semaphore.
If the process has a process, text, or data lock, an unlock
is performed [see plock(2)].
An accounting record is written on the accounting file if
the system's accounting routine is enabled [see acct(2)].
If the process is a controlling process [see intro(2)], the
SIGHUP signal is sent to each process that has a process
group ID equal to that of the calling process.
A death of child signal is sent to the parent.
If the exit of this process causes a process group to become
an orphaned process group [see intro(2)] and any member of
the newly orphaned process group is stopped, the SIGHUP
signal, followed by the SIGCONT signal is sent to each
member of the newly orphaned process group.
The C function exit may cause cleanup actions before the
process exits. The function _exit circumvents all cleanup.
SEE ALSO
acct(2), intro(2), plock(2), semop(2), signal(2), sigset(2),
wait(2), waitpid(2).
WARNING
See WARNING in signal(2).
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EXIT(2) EXIT(2)
DIAGNOSTICS
None. There can be no return from an exit system call.
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