corosync/man/sam_start.3

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.TH "SAM_START" 3 "30/04/2010" "corosync Man Page" "Corosync Cluster Engine Programmer's Manual"

.SH NAME
.P
sam_start \- Start health checking

.SH SYNOPSIS
.P
\fB#include <corosync/sam.h>\fR

.P
\fBcs_error_t sam_start (void);\fR

.SH DESCRIPTION
.P
The \fBsam_start\fR function is used to start health checking of application.
After calling this function, the active process needs to send healthchecks
within the registered time interval by calling \fBsam_hc_send(3)\fR.  If
event driven healthchecking is configured by calling \fBsam_register(3)\fR,
an internal thread will be created and send health check confirmations four
times per \fItime_interval\fR.

.P
Application must be registered by calling \fBsam_register(3)\fR before this
function can be called.

.P
An application can always stop health checking by calling the \fBsam_stop(3)\fR
function.

.P
If SAM is initialized with quorum policy \fISAM_RECOVERY_POLICY_QUIT\fR or
\fISAM_RECOVERY_POLICY_RESTART\fR \fBsam_start\fR will block until corosync
becomes quorate.

.SH RETURN VALUE
.P
This call return CS_OK value if successful, otherwise and error is returned. If
SAM is initialized with quorum policy, returned error can also be quorum error.

.SH ERRORS
.TP
CS_ERR_BAD_HANDLE
component was not registered by calling \fBsam_register(3)\fR function.

.SH "SEE ALSO"
.BR sam_hc_send (3),
.BR sam_stop (3),
.BR sam_register (3),
.BR sam_hc_callback_register (3)