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   &#160;<span id="projectnumber">1.8.20</span>
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<div class="fragment"><pre class="fragment"><a name="l00001"></a>00001 <span class="comment">/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/</span>
<a name="l00002"></a>00002 
<a name="l00003"></a>00003 <span class="preprocessor">#ifndef foosddaemonhfoo</span>
<a name="l00004"></a>00004 <span class="preprocessor"></span><span class="preprocessor">#define foosddaemonhfoo</span>
<a name="l00005"></a>00005 <span class="preprocessor"></span>
<a name="l00006"></a>00006 <span class="comment">/***</span>
<a name="l00007"></a>00007 <span class="comment">  Copyright 2010 Lennart Poettering</span>
<a name="l00008"></a>00008 <span class="comment"></span>
<a name="l00009"></a>00009 <span class="comment">  Permission is hereby granted, free of charge, to any person</span>
<a name="l00010"></a>00010 <span class="comment">  obtaining a copy of this software and associated documentation files</span>
<a name="l00011"></a>00011 <span class="comment">  (the &quot;Software&quot;), to deal in the Software without restriction,</span>
<a name="l00012"></a>00012 <span class="comment">  including without limitation the rights to use, copy, modify, merge,</span>
<a name="l00013"></a>00013 <span class="comment">  publish, distribute, sublicense, and/or sell copies of the Software,</span>
<a name="l00014"></a>00014 <span class="comment">  and to permit persons to whom the Software is furnished to do so,</span>
<a name="l00015"></a>00015 <span class="comment">  subject to the following conditions:</span>
<a name="l00016"></a>00016 <span class="comment"></span>
<a name="l00017"></a>00017 <span class="comment">  The above copyright notice and this permission notice shall be</span>
<a name="l00018"></a>00018 <span class="comment">  included in all copies or substantial portions of the Software.</span>
<a name="l00019"></a>00019 <span class="comment"></span>
<a name="l00020"></a>00020 <span class="comment">  THE SOFTWARE IS PROVIDED &quot;AS IS&quot;, WITHOUT WARRANTY OF ANY KIND,</span>
<a name="l00021"></a>00021 <span class="comment">  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF</span>
<a name="l00022"></a>00022 <span class="comment">  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND</span>
<a name="l00023"></a>00023 <span class="comment">  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS</span>
<a name="l00024"></a>00024 <span class="comment">  BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN</span>
<a name="l00025"></a>00025 <span class="comment">  ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN</span>
<a name="l00026"></a>00026 <span class="comment">  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE</span>
<a name="l00027"></a>00027 <span class="comment">  SOFTWARE.</span>
<a name="l00028"></a>00028 <span class="comment">***/</span>
<a name="l00029"></a>00029 
<a name="l00030"></a>00030 <span class="preprocessor">#include &lt;sys/types.h&gt;</span>
<a name="l00031"></a>00031 <span class="preprocessor">#include &lt;inttypes.h&gt;</span>
<a name="l00032"></a>00032 
<a name="l00033"></a>00033 <span class="preprocessor">#ifdef __cplusplus</span>
<a name="l00034"></a>00034 <span class="preprocessor"></span><span class="keyword">extern</span> <span class="stringliteral">&quot;C&quot;</span> {
<a name="l00035"></a>00035 <span class="preprocessor">#endif</span>
<a name="l00036"></a>00036 <span class="preprocessor"></span>
<a name="l00037"></a>00037 <span class="comment">/*</span>
<a name="l00038"></a>00038 <span class="comment">  Reference implementation of a few systemd related interfaces for</span>
<a name="l00039"></a>00039 <span class="comment">  writing daemons. These interfaces are trivial to implement. To</span>
<a name="l00040"></a>00040 <span class="comment">  simplify porting we provide this reference implementation.</span>
<a name="l00041"></a>00041 <span class="comment">  Applications are welcome to reimplement the algorithms described</span>
<a name="l00042"></a>00042 <span class="comment">  here if they do not want to include these two source files.</span>
<a name="l00043"></a>00043 <span class="comment"></span>
<a name="l00044"></a>00044 <span class="comment">  The following functionality is provided:</span>
<a name="l00045"></a>00045 <span class="comment"></span>
<a name="l00046"></a>00046 <span class="comment">  - Support for logging with log levels on stderr</span>
<a name="l00047"></a>00047 <span class="comment">  - File descriptor passing for socket-based activation</span>
<a name="l00048"></a>00048 <span class="comment">  - Daemon startup and status notification</span>
<a name="l00049"></a>00049 <span class="comment">  - Detection of systemd boots</span>
<a name="l00050"></a>00050 <span class="comment"></span>
<a name="l00051"></a>00051 <span class="comment">  You may compile this with -DDISABLE_SYSTEMD to disable systemd</span>
<a name="l00052"></a>00052 <span class="comment">  support. This makes all those calls NOPs that are directly related to</span>
<a name="l00053"></a>00053 <span class="comment">  systemd (i.e. only sd_is_xxx() will stay useful).</span>
<a name="l00054"></a>00054 <span class="comment"></span>
<a name="l00055"></a>00055 <span class="comment">  Since this is drop-in code we don&#39;t want any of our symbols to be</span>
<a name="l00056"></a>00056 <span class="comment">  exported in any case. Hence we declare hidden visibility for all of</span>
<a name="l00057"></a>00057 <span class="comment">  them.</span>
<a name="l00058"></a>00058 <span class="comment"></span>
<a name="l00059"></a>00059 <span class="comment">  You may find an up-to-date version of these source files online:</span>
<a name="l00060"></a>00060 <span class="comment"></span>
<a name="l00061"></a>00061 <span class="comment">  http://cgit.freedesktop.org/systemd/systemd/plain/src/systemd/sd-daemon.h</span>
<a name="l00062"></a>00062 <span class="comment">  http://cgit.freedesktop.org/systemd/systemd/plain/src/libsystemd-daemon/sd-daemon.c</span>
<a name="l00063"></a>00063 <span class="comment"></span>
<a name="l00064"></a>00064 <span class="comment">  This should compile on non-Linux systems, too, but with the</span>
<a name="l00065"></a>00065 <span class="comment">  exception of the sd_is_xxx() calls all functions will become NOPs.</span>
<a name="l00066"></a>00066 <span class="comment"></span>
<a name="l00067"></a>00067 <span class="comment">  See sd-daemon(3) for more information.</span>
<a name="l00068"></a>00068 <span class="comment">*/</span>
<a name="l00069"></a>00069 
<a name="l00070"></a>00070 <span class="preprocessor">#ifndef _sd_printf_attr_</span>
<a name="l00071"></a>00071 <span class="preprocessor"></span><span class="preprocessor">#if __GNUC__ &gt;= 4</span>
<a name="l00072"></a>00072 <span class="preprocessor"></span><span class="preprocessor">#define _sd_printf_attr_(a,b) __attribute__ ((format (printf, a, b)))</span>
<a name="l00073"></a>00073 <span class="preprocessor"></span><span class="preprocessor">#else</span>
<a name="l00074"></a>00074 <span class="preprocessor"></span><span class="preprocessor">#define _sd_printf_attr_(a,b)</span>
<a name="l00075"></a>00075 <span class="preprocessor"></span><span class="preprocessor">#endif</span>
<a name="l00076"></a>00076 <span class="preprocessor"></span><span class="preprocessor">#endif</span>
<a name="l00077"></a>00077 <span class="preprocessor"></span>
<a name="l00078"></a>00078 <span class="comment">/*</span>
<a name="l00079"></a>00079 <span class="comment">  Log levels for usage on stderr:</span>
<a name="l00080"></a>00080 <span class="comment"></span>
<a name="l00081"></a>00081 <span class="comment">          fprintf(stderr, SD_NOTICE &quot;Hello World!\n&quot;);</span>
<a name="l00082"></a>00082 <span class="comment"></span>
<a name="l00083"></a>00083 <span class="comment">  This is similar to printk() usage in the kernel.</span>
<a name="l00084"></a>00084 <span class="comment">*/</span>
<a name="l00085"></a>00085 <span class="preprocessor">#define SD_EMERG   &quot;&lt;0&gt;&quot;  </span><span class="comment">/* system is unusable */</span>
<a name="l00086"></a>00086 <span class="preprocessor">#define SD_ALERT   &quot;&lt;1&gt;&quot;  </span><span class="comment">/* action must be taken immediately */</span>
<a name="l00087"></a>00087 <span class="preprocessor">#define SD_CRIT    &quot;&lt;2&gt;&quot;  </span><span class="comment">/* critical conditions */</span>
<a name="l00088"></a>00088 <span class="preprocessor">#define SD_ERR     &quot;&lt;3&gt;&quot;  </span><span class="comment">/* error conditions */</span>
<a name="l00089"></a>00089 <span class="preprocessor">#define SD_WARNING &quot;&lt;4&gt;&quot;  </span><span class="comment">/* warning conditions */</span>
<a name="l00090"></a>00090 <span class="preprocessor">#define SD_NOTICE  &quot;&lt;5&gt;&quot;  </span><span class="comment">/* normal but significant condition */</span>
<a name="l00091"></a>00091 <span class="preprocessor">#define SD_INFO    &quot;&lt;6&gt;&quot;  </span><span class="comment">/* informational */</span>
<a name="l00092"></a>00092 <span class="preprocessor">#define SD_DEBUG   &quot;&lt;7&gt;&quot;  </span><span class="comment">/* debug-level messages */</span>
<a name="l00093"></a>00093 
<a name="l00094"></a>00094 <span class="comment">/* The first passed file descriptor is fd 3 */</span>
<a name="l00095"></a>00095 <span class="preprocessor">#define SD_LISTEN_FDS_START 3</span>
<a name="l00096"></a>00096 <span class="preprocessor"></span>
<a name="l00097"></a>00097 <span class="comment">/*</span>
<a name="l00098"></a>00098 <span class="comment">  Returns how many file descriptors have been passed, or a negative</span>
<a name="l00099"></a>00099 <span class="comment">  errno code on failure. Optionally, removes the $LISTEN_FDS and</span>
<a name="l00100"></a>00100 <span class="comment">  $LISTEN_PID file descriptors from the environment (recommended, but</span>
<a name="l00101"></a>00101 <span class="comment">  problematic in threaded environments). If r is the return value of</span>
<a name="l00102"></a>00102 <span class="comment">  this function you&#39;ll find the file descriptors passed as fds</span>
<a name="l00103"></a>00103 <span class="comment">  SD_LISTEN_FDS_START to SD_LISTEN_FDS_START+r-1. Returns a negative</span>
<a name="l00104"></a>00104 <span class="comment">  errno style error code on failure. This function call ensures that</span>
<a name="l00105"></a>00105 <span class="comment">  the FD_CLOEXEC flag is set for the passed file descriptors, to make</span>
<a name="l00106"></a>00106 <span class="comment">  sure they are not passed on to child processes. If FD_CLOEXEC shall</span>
<a name="l00107"></a>00107 <span class="comment">  not be set, the caller needs to unset it after this call for all file</span>
<a name="l00108"></a>00108 <span class="comment">  descriptors that are used.</span>
<a name="l00109"></a>00109 <span class="comment"></span>
<a name="l00110"></a>00110 <span class="comment">  See sd_listen_fds(3) for more information.</span>
<a name="l00111"></a>00111 <span class="comment">*/</span>
<a name="l00112"></a>00112 <span class="keywordtype">int</span> sd_listen_fds(<span class="keywordtype">int</span> unset_environment);
<a name="l00113"></a>00113 
<a name="l00114"></a>00114 <span class="comment">/*</span>
<a name="l00115"></a>00115 <span class="comment">  Helper call for identifying a passed file descriptor. Returns 1 if</span>
<a name="l00116"></a>00116 <span class="comment">  the file descriptor is a FIFO in the file system stored under the</span>
<a name="l00117"></a>00117 <span class="comment">  specified path, 0 otherwise. If path is NULL a path name check will</span>
<a name="l00118"></a>00118 <span class="comment">  not be done and the call only verifies if the file descriptor</span>
<a name="l00119"></a>00119 <span class="comment">  refers to a FIFO. Returns a negative errno style error code on</span>
<a name="l00120"></a>00120 <span class="comment">  failure.</span>
<a name="l00121"></a>00121 <span class="comment"></span>
<a name="l00122"></a>00122 <span class="comment">  See sd_is_fifo(3) for more information.</span>
<a name="l00123"></a>00123 <span class="comment">*/</span>
<a name="l00124"></a>00124 <span class="keywordtype">int</span> sd_is_fifo(<span class="keywordtype">int</span> fd, <span class="keyword">const</span> <span class="keywordtype">char</span> *path);
<a name="l00125"></a>00125 
<a name="l00126"></a>00126 <span class="comment">/*</span>
<a name="l00127"></a>00127 <span class="comment">  Helper call for identifying a passed file descriptor. Returns 1 if</span>
<a name="l00128"></a>00128 <span class="comment">  the file descriptor is a special character device on the file</span>
<a name="l00129"></a>00129 <span class="comment">  system stored under the specified path, 0 otherwise.</span>
<a name="l00130"></a>00130 <span class="comment">  If path is NULL a path name check will not be done and the call</span>
<a name="l00131"></a>00131 <span class="comment">  only verifies if the file descriptor refers to a special character.</span>
<a name="l00132"></a>00132 <span class="comment">  Returns a negative errno style error code on failure.</span>
<a name="l00133"></a>00133 <span class="comment"></span>
<a name="l00134"></a>00134 <span class="comment">  See sd_is_special(3) for more information.</span>
<a name="l00135"></a>00135 <span class="comment">*/</span>
<a name="l00136"></a>00136 <span class="keywordtype">int</span> sd_is_special(<span class="keywordtype">int</span> fd, <span class="keyword">const</span> <span class="keywordtype">char</span> *path);
<a name="l00137"></a>00137 
<a name="l00138"></a>00138 <span class="comment">/*</span>
<a name="l00139"></a>00139 <span class="comment">  Helper call for identifying a passed file descriptor. Returns 1 if</span>
<a name="l00140"></a>00140 <span class="comment">  the file descriptor is a socket of the specified family (AF_INET,</span>
<a name="l00141"></a>00141 <span class="comment">  ...) and type (SOCK_DGRAM, SOCK_STREAM, ...), 0 otherwise. If</span>
<a name="l00142"></a>00142 <span class="comment">  family is 0 a socket family check will not be done. If type is 0 a</span>
<a name="l00143"></a>00143 <span class="comment">  socket type check will not be done and the call only verifies if</span>
<a name="l00144"></a>00144 <span class="comment">  the file descriptor refers to a socket. If listening is &gt; 0 it is</span>
<a name="l00145"></a>00145 <span class="comment">  verified that the socket is in listening mode. (i.e. listen() has</span>
<a name="l00146"></a>00146 <span class="comment">  been called) If listening is == 0 it is verified that the socket is</span>
<a name="l00147"></a>00147 <span class="comment">  not in listening mode. If listening is &lt; 0 no listening mode check</span>
<a name="l00148"></a>00148 <span class="comment">  is done. Returns a negative errno style error code on failure.</span>
<a name="l00149"></a>00149 <span class="comment"></span>
<a name="l00150"></a>00150 <span class="comment">  See sd_is_socket(3) for more information.</span>
<a name="l00151"></a>00151 <span class="comment">*/</span>
<a name="l00152"></a>00152 <span class="keywordtype">int</span> sd_is_socket(<span class="keywordtype">int</span> fd, <span class="keywordtype">int</span> family, <span class="keywordtype">int</span> type, <span class="keywordtype">int</span> listening);
<a name="l00153"></a>00153 
<a name="l00154"></a>00154 <span class="comment">/*</span>
<a name="l00155"></a>00155 <span class="comment">  Helper call for identifying a passed file descriptor. Returns 1 if</span>
<a name="l00156"></a>00156 <span class="comment">  the file descriptor is an Internet socket, of the specified family</span>
<a name="l00157"></a>00157 <span class="comment">  (either AF_INET or AF_INET6) and the specified type (SOCK_DGRAM,</span>
<a name="l00158"></a>00158 <span class="comment">  SOCK_STREAM, ...), 0 otherwise. If version is 0 a protocol version</span>
<a name="l00159"></a>00159 <span class="comment">  check is not done. If type is 0 a socket type check will not be</span>
<a name="l00160"></a>00160 <span class="comment">  done. If port is 0 a socket port check will not be done. The</span>
<a name="l00161"></a>00161 <span class="comment">  listening flag is used the same way as in sd_is_socket(). Returns a</span>
<a name="l00162"></a>00162 <span class="comment">  negative errno style error code on failure.</span>
<a name="l00163"></a>00163 <span class="comment"></span>
<a name="l00164"></a>00164 <span class="comment">  See sd_is_socket_inet(3) for more information.</span>
<a name="l00165"></a>00165 <span class="comment">*/</span>
<a name="l00166"></a>00166 <span class="keywordtype">int</span> sd_is_socket_inet(<span class="keywordtype">int</span> fd, <span class="keywordtype">int</span> family, <span class="keywordtype">int</span> type, <span class="keywordtype">int</span> listening, uint16_t port);
<a name="l00167"></a>00167 
<a name="l00168"></a>00168 <span class="comment">/*</span>
<a name="l00169"></a>00169 <span class="comment">  Helper call for identifying a passed file descriptor. Returns 1 if</span>
<a name="l00170"></a>00170 <span class="comment">  the file descriptor is an AF_UNIX socket of the specified type</span>
<a name="l00171"></a>00171 <span class="comment">  (SOCK_DGRAM, SOCK_STREAM, ...) and path, 0 otherwise. If type is 0</span>
<a name="l00172"></a>00172 <span class="comment">  a socket type check will not be done. If path is NULL a socket path</span>
<a name="l00173"></a>00173 <span class="comment">  check will not be done. For normal AF_UNIX sockets set length to</span>
<a name="l00174"></a>00174 <span class="comment">  0. For abstract namespace sockets set length to the length of the</span>
<a name="l00175"></a>00175 <span class="comment">  socket name (including the initial 0 byte), and pass the full</span>
<a name="l00176"></a>00176 <span class="comment">  socket path in path (including the initial 0 byte). The listening</span>
<a name="l00177"></a>00177 <span class="comment">  flag is used the same way as in sd_is_socket(). Returns a negative</span>
<a name="l00178"></a>00178 <span class="comment">  errno style error code on failure.</span>
<a name="l00179"></a>00179 <span class="comment"></span>
<a name="l00180"></a>00180 <span class="comment">  See sd_is_socket_unix(3) for more information.</span>
<a name="l00181"></a>00181 <span class="comment">*/</span>
<a name="l00182"></a>00182 <span class="keywordtype">int</span> sd_is_socket_unix(<span class="keywordtype">int</span> fd, <span class="keywordtype">int</span> type, <span class="keywordtype">int</span> listening, <span class="keyword">const</span> <span class="keywordtype">char</span> *path, <span class="keywordtype">size_t</span> length);
<a name="l00183"></a>00183 
<a name="l00184"></a>00184 <span class="comment">/*</span>
<a name="l00185"></a>00185 <span class="comment">  Helper call for identifying a passed file descriptor. Returns 1 if</span>
<a name="l00186"></a>00186 <span class="comment">  the file descriptor is a POSIX Message Queue of the specified name,</span>
<a name="l00187"></a>00187 <span class="comment">  0 otherwise. If path is NULL a message queue name check is not</span>
<a name="l00188"></a>00188 <span class="comment">  done. Returns a negative errno style error code on failure.</span>
<a name="l00189"></a>00189 <span class="comment">*/</span>
<a name="l00190"></a>00190 <span class="keywordtype">int</span> sd_is_mq(<span class="keywordtype">int</span> fd, <span class="keyword">const</span> <span class="keywordtype">char</span> *path);
<a name="l00191"></a>00191 
<a name="l00192"></a>00192 <span class="comment">/*</span>
<a name="l00193"></a>00193 <span class="comment">  Informs systemd about changed daemon state. This takes a number of</span>
<a name="l00194"></a>00194 <span class="comment">  newline separated environment-style variable assignments in a</span>
<a name="l00195"></a>00195 <span class="comment">  string. The following variables are known:</span>
<a name="l00196"></a>00196 <span class="comment"></span>
<a name="l00197"></a>00197 <span class="comment">     READY=1      Tells systemd that daemon startup is finished (only</span>
<a name="l00198"></a>00198 <span class="comment">                  relevant for services of Type=notify). The passed</span>
<a name="l00199"></a>00199 <span class="comment">                  argument is a boolean &quot;1&quot; or &quot;0&quot;. Since there is</span>
<a name="l00200"></a>00200 <span class="comment">                  little value in signaling non-readiness the only</span>
<a name="l00201"></a>00201 <span class="comment">                  value daemons should send is &quot;READY=1&quot;.</span>
<a name="l00202"></a>00202 <span class="comment"></span>
<a name="l00203"></a>00203 <span class="comment">     STATUS=...   Passes a single-line status string back to systemd</span>
<a name="l00204"></a>00204 <span class="comment">                  that describes the daemon state. This is free-from</span>
<a name="l00205"></a>00205 <span class="comment">                  and can be used for various purposes: general state</span>
<a name="l00206"></a>00206 <span class="comment">                  feedback, fsck-like programs could pass completion</span>
<a name="l00207"></a>00207 <span class="comment">                  percentages and failing programs could pass a human</span>
<a name="l00208"></a>00208 <span class="comment">                  readable error message. Example: &quot;STATUS=Completed</span>
<a name="l00209"></a>00209 <span class="comment">                  66% of file system check...&quot;</span>
<a name="l00210"></a>00210 <span class="comment"></span>
<a name="l00211"></a>00211 <span class="comment">     ERRNO=...    If a daemon fails, the errno-style error code,</span>
<a name="l00212"></a>00212 <span class="comment">                  formatted as string. Example: &quot;ERRNO=2&quot; for ENOENT.</span>
<a name="l00213"></a>00213 <span class="comment"></span>
<a name="l00214"></a>00214 <span class="comment">     BUSERROR=... If a daemon fails, the D-Bus error-style error</span>
<a name="l00215"></a>00215 <span class="comment">                  code. Example: &quot;BUSERROR=org.freedesktop.DBus.Error.TimedOut&quot;</span>
<a name="l00216"></a>00216 <span class="comment"></span>
<a name="l00217"></a>00217 <span class="comment">     MAINPID=...  The main pid of a daemon, in case systemd did not</span>
<a name="l00218"></a>00218 <span class="comment">                  fork off the process itself. Example: &quot;MAINPID=4711&quot;</span>
<a name="l00219"></a>00219 <span class="comment"></span>
<a name="l00220"></a>00220 <span class="comment">     WATCHDOG=1   Tells systemd to update the watchdog timestamp.</span>
<a name="l00221"></a>00221 <span class="comment">                  Services using this feature should do this in</span>
<a name="l00222"></a>00222 <span class="comment">                  regular intervals. A watchdog framework can use the</span>
<a name="l00223"></a>00223 <span class="comment">                  timestamps to detect failed services.</span>
<a name="l00224"></a>00224 <span class="comment"></span>
<a name="l00225"></a>00225 <span class="comment">  Daemons can choose to send additional variables. However, it is</span>
<a name="l00226"></a>00226 <span class="comment">  recommended to prefix variable names not listed above with X_.</span>
<a name="l00227"></a>00227 <span class="comment"></span>
<a name="l00228"></a>00228 <span class="comment">  Returns a negative errno-style error code on failure. Returns &gt; 0</span>
<a name="l00229"></a>00229 <span class="comment">  if systemd could be notified, 0 if it couldn&#39;t possibly because</span>
<a name="l00230"></a>00230 <span class="comment">  systemd is not running.</span>
<a name="l00231"></a>00231 <span class="comment"></span>
<a name="l00232"></a>00232 <span class="comment">  Example: When a daemon finished starting up, it could issue this</span>
<a name="l00233"></a>00233 <span class="comment">  call to notify systemd about it:</span>
<a name="l00234"></a>00234 <span class="comment"></span>
<a name="l00235"></a>00235 <span class="comment">     sd_notify(0, &quot;READY=1&quot;);</span>
<a name="l00236"></a>00236 <span class="comment"></span>
<a name="l00237"></a>00237 <span class="comment">  See sd_notifyf() for more complete examples.</span>
<a name="l00238"></a>00238 <span class="comment"></span>
<a name="l00239"></a>00239 <span class="comment">  See sd_notify(3) for more information.</span>
<a name="l00240"></a>00240 <span class="comment">*/</span>
<a name="l00241"></a>00241 <span class="keywordtype">int</span> sd_notify(<span class="keywordtype">int</span> unset_environment, <span class="keyword">const</span> <span class="keywordtype">char</span> *state);
<a name="l00242"></a>00242 
<a name="l00243"></a>00243 <span class="comment">/*</span>
<a name="l00244"></a>00244 <span class="comment">  Similar to sd_notify() but takes a format string.</span>
<a name="l00245"></a>00245 <span class="comment"></span>
<a name="l00246"></a>00246 <span class="comment">  Example 1: A daemon could send the following after initialization:</span>
<a name="l00247"></a>00247 <span class="comment"></span>
<a name="l00248"></a>00248 <span class="comment">     sd_notifyf(0, &quot;READY=1\n&quot;</span>
<a name="l00249"></a>00249 <span class="comment">                   &quot;STATUS=Processing requests...\n&quot;</span>
<a name="l00250"></a>00250 <span class="comment">                   &quot;MAINPID=%lu&quot;,</span>
<a name="l00251"></a>00251 <span class="comment">                   (unsigned long) getpid());</span>
<a name="l00252"></a>00252 <span class="comment"></span>
<a name="l00253"></a>00253 <span class="comment">  Example 2: A daemon could send the following shortly before</span>
<a name="l00254"></a>00254 <span class="comment">  exiting, on failure:</span>
<a name="l00255"></a>00255 <span class="comment"></span>
<a name="l00256"></a>00256 <span class="comment">     sd_notifyf(0, &quot;STATUS=Failed to start up: %s\n&quot;</span>
<a name="l00257"></a>00257 <span class="comment">                   &quot;ERRNO=%i&quot;,</span>
<a name="l00258"></a>00258 <span class="comment">                   strerror(errno),</span>
<a name="l00259"></a>00259 <span class="comment">                   errno);</span>
<a name="l00260"></a>00260 <span class="comment"></span>
<a name="l00261"></a>00261 <span class="comment">  See sd_notifyf(3) for more information.</span>
<a name="l00262"></a>00262 <span class="comment">*/</span>
<a name="l00263"></a>00263 <span class="keywordtype">int</span> sd_notifyf(<span class="keywordtype">int</span> unset_environment, <span class="keyword">const</span> <span class="keywordtype">char</span> *format, ...) _sd_printf_attr_(2,3);
<a name="l00264"></a>00264 
<a name="l00265"></a>00265 <span class="comment">/*</span>
<a name="l00266"></a>00266 <span class="comment">  Returns &gt; 0 if the system was booted with systemd. Returns &lt; 0 on</span>
<a name="l00267"></a>00267 <span class="comment">  error. Returns 0 if the system was not booted with systemd. Note</span>
<a name="l00268"></a>00268 <span class="comment">  that all of the functions above handle non-systemd boots just</span>
<a name="l00269"></a>00269 <span class="comment">  fine. You should NOT protect them with a call to this function. Also</span>
<a name="l00270"></a>00270 <span class="comment">  note that this function checks whether the system, not the user</span>
<a name="l00271"></a>00271 <span class="comment">  session is controlled by systemd. However the functions above work</span>
<a name="l00272"></a>00272 <span class="comment">  for both user and system services.</span>
<a name="l00273"></a>00273 <span class="comment"></span>
<a name="l00274"></a>00274 <span class="comment">  See sd_booted(3) for more information.</span>
<a name="l00275"></a>00275 <span class="comment">*/</span>
<a name="l00276"></a>00276 <span class="keywordtype">int</span> sd_booted(<span class="keywordtype">void</span>);
<a name="l00277"></a>00277 
<a name="l00278"></a>00278 <span class="preprocessor">#ifdef __cplusplus</span>
<a name="l00279"></a>00279 <span class="preprocessor"></span>}
<a name="l00280"></a>00280 <span class="preprocessor">#endif</span>
<a name="l00281"></a>00281 <span class="preprocessor"></span>
<a name="l00282"></a>00282 <span class="preprocessor">#endif</span>
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