atcheckpoint(3C)atcheckpoint(3C)NAME
atcheckpoint, atrestart - add checkpoint and restart (CPR) event handlers
SYNOPSIS
#include <stdlib.h>
int atcheckpoint(void (*func)(void));
int atrestart(void (*func)(void));
DESCRIPTION
These functions are used to register event handlers for checkpoint and
restart, and activate CPR signal handling. The atcheckpoint() routine
adds the function func() to the list of functions to be called without
arguments upon receipt of checkpoint; see ckpt_create(3). Similarly, the
atrestart() routine registers the callback function func() for a restart
event; see ckpt_restart(3). At checkpoint or restart time, registered
functions are called in the same order as their registration.
These functions are recommended for use during initialization when
applications expect to be checkpointed but contain checkpoint-unsafe
objects; see cpr(1) for a list of unsafe objects. An application may
register multiple checkpoint and/or restart event handlers to be called
when checkpoint and/or restart occur, for example to disconnect socket
connections at checkpoint time and reconnect them at restart time.
DIAGNOSTICS
The atcheckpoint() and atrestart() routines return 0 if the registration
succeeds, or -1 with errno set if registration fails. The maximum number
of handlers allowed for each process (or thread) is 32.
SEE ALSOcpr(1), cview(1), ckpt_create(3), ckpt_remove(3), ckpt_restart(3),
ckpt_stat(3)
IRIX Checkpoint and Restart Operation Guide
Page 1
