/* This file is part of the YAZ toolkit.
 * Copyright (C) 1995-2009 Index Data.
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of Index Data nor the names of its contributors
 *       may be used to endorse or promote products derived from this
 *       software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * \file daemon.h
 * \brief Unix daemon management
 */

#ifndef YAZ_DAEMON_H
#define YAZ_DAEMON_H

#include <stdio.h>
#include <yaz/yconfig.h>

YAZ_BEGIN_CDECL

#define YAZ_DAEMON_FORK 1
#define YAZ_DAEMON_DEBUG 2
#define YAZ_DAEMON_KEEPALIVE 4

/** \brief daemon utility.
    \param progname program name for logging purposes.
    \param flags flags which is a bit-wise combination of YAZ_DAEMON_..
    \param work working handler (which may be running in different process)
    \param data opaque data to be passed to work handler
    \param pidfile filename with Process-ID (NULL for no file)
    \param uid effective user ID for handler (NULL for no same as caller)
    \returns 0 for success, non-zero for failure.

    This function puts calls work handler which is supposed to carry
    out a daemon service with a possible changed User ID and in a
    child process.

    Flag YAZ_DAEMON_FORK: Puts the service in the background on Unix.

    Flag YAZ_DAEMON_DEBUG: Puts the service in debug mode (no fork at all).

    Flag YAZ_DAEMON_KEEPALIVE: Repeatedly calls work handler if it makes a 
    "fatal" error.
*/
YAZ_EXPORT
int yaz_daemon(const char *progname,
               unsigned int flags,
               void (*work)(void *data), void *data,
               const char *pidfile, const char *uid);

YAZ_END_CDECL

#endif
/*
 * Local variables:
 * c-basic-offset: 4
 * c-file-style: "Stroustrup"
 * indent-tabs-mode: nil
 * End:
 * vim: shiftwidth=4 tabstop=8 expandtab
 */

