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  82 ><H1
  83 CLASS="SECT1"
  84 ><A
  85 NAME="POSIX-EXECUTION-SCHEDULING">Execution Scheduling &#0091;POSIX Section 13&#0093;</H1
  86 ><DIV
  87 CLASS="SECT2"
  88 ><H2
  89 CLASS="SECT2"
  90 ><A
  91 NAME="AEN13195">Functions Implemented</H2
  92 ><TABLE
  93 BORDER="5"
  94 BGCOLOR="#E0E0F0"
  95 WIDTH="70%"
  96 ><TR
  97 ><TD
  98 ><PRE
  99 CLASS="SCREEN"
 100 >int sched&#0095;yield(void);
 101 int sched&#0095;get&#0095;priority&#0095;max(int policy);
 102 int sched&#0095;get&#0095;priority&#0095;min(int policy);
 103 int sched&#0095;rr&#0095;get&#0095;interval(pid&#0095;t pid, struct timespec &#0042;t);
 104 int pthread&#0095;attr&#0095;setscope(pthread&#0095;attr&#0095;t &#0042;attr, int scope);
 105 int pthread&#0095;attr&#0095;getscope(const pthread&#0095;attr&#0095;t &#0042;attr, int &#0042;scope);
 106 int pthread&#0095;attr&#0095;setinheritsched(pthread&#0095;attr&#0095;t &#0042;attr, int inherit);
 107 int pthread&#0095;attr&#0095;getinheritsched(const pthread&#0095;attr&#0095;t &#0042;attr, int &#0042;inherit);
 108 int pthread&#0095;attr&#0095;setschedpolicy(pthread&#0095;attr&#0095;t &#0042;attr, int policy);
 109 int pthread&#0095;attr&#0095;getschedpolicy(const pthread&#0095;attr&#0095;t &#0042;attr, int &#0042;policy);
 110 int pthread&#0095;attr&#0095;setschedparam( pthread&#0095;attr&#0095;t &#0042;attr, const struct sched&#0095;param &#0042;param);
 111 int pthread&#0095;attr&#0095;getschedparam( const pthread&#0095;attr&#0095;t &#0042;attr,
 112                                 struct sched&#0095;param &#0042;param);
 113 int pthread&#0095;setschedparam(pthread&#0095;t thread, int policy,
 114                           const struct sched&#0095;param &#0042;param);
 115 int pthread&#0095;getschedparam(pthread&#0095;t thread, int &#0042;policy,
 116                           struct sched&#0095;param &#0042;param);
 117 int pthread&#0095;mutexattr&#0095;setprotocol( pthread&#0095;mutexattr&#0095;t &#0042;attr,
 118                                    int protocol);
 119 int pthread&#0095;mutexattr&#0095;getprotocol( pthread&#0095;mutexattr&#0095;t &#0042;attr,
 120                                    int &#0042;protocol);
 121 int pthread&#0095;mutexattr&#0095;setprioceiling( pthread&#0095;mutexattr&#0095;t &#0042;attr,
 122                                       int prioceiling);
 123 int pthread&#0095;mutexattr&#0095;getprioceiling( pthread&#0095;mutexattr&#0095;t &#0042;attr,
 124                                       int &#0042;prioceiling);
 125 int pthread&#0095;mutex&#0095;setprioceiling( pthread&#0095;mutex&#0095;t &#0042;mutex,
 126                                   int prioceiling,
 127                                   int &#0042;old&#0095;ceiling);
 128 int pthread&#0095;mutex&#0095;getprioceiling( pthread&#0095;mutex&#0095;t &#0042;mutex,
 129                                   int &#0042;prioceiling);</PRE
 130 ></TD
 131 ></TR
 132 ></TABLE
 133 ></DIV
 134 ><DIV
 135 CLASS="SECT2"
 136 ><H2
 137 CLASS="SECT2"
 138 ><A
 139 NAME="AEN13198">Functions Omitted</H2
 140 ><TABLE
 141 BORDER="5"
 142 BGCOLOR="#E0E0F0"
 143 WIDTH="70%"
 144 ><TR
 145 ><TD
 146 ><PRE
 147 CLASS="SCREEN"
 148 >int sched&#0095;setparam(pid&#0095;t pid, const struct sched&#0095;param &#0042;param);
 149 int sched&#0095;getparam(pid&#0095;t pid, struct sched&#0095;param &#0042;param);
 150 int sched&#0095;setscheduler(pid&#0095;t pid, int policy,
 151                        const struct sched&#0095;param &#0042;param);
 152 int sched&#0095;getscheduler(pid&#0095;t pid);</PRE
 153 ></TD
 154 ></TR
 155 ></TABLE
 156 ></DIV
 157 ><DIV
 158 CLASS="SECT2"
 159 ><H2
 160 CLASS="SECT2"
 161 ><A
 162 NAME="AEN13201">Notes</H2
 163 ><P
 164 ></P
 165 ><UL
 166 ><LI
 167 ><P
 168 >         The functions <SPAN
 169 CLASS="emphasis"
 170 ><I
 171 CLASS="EMPHASIS"
 172 >sched&#0095;setparam()</I
 173 ></SPAN
 174 >,
 175           <SPAN
 176 CLASS="emphasis"
 177 ><I
 178 CLASS="EMPHASIS"
 179 >sched&#0095;getparam()</I
 180 ></SPAN
 181 >,
 182           <SPAN
 183 CLASS="emphasis"
 184 ><I
 185 CLASS="EMPHASIS"
 186 >sched&#0095;setscheduler()</I
 187 ></SPAN
 188 > and
 189           <SPAN
 190 CLASS="emphasis"
 191 ><I
 192 CLASS="EMPHASIS"
 193 >sched&#0095;getscheduler()</I
 194 ></SPAN
 195 > are present
 196           but always return an error.
 197           </P
 198 ></LI
 199 ><LI
 200 ><P
 201 >         The scheduler policy <SPAN
 202 CLASS="emphasis"
 203 ><I
 204 CLASS="EMPHASIS"
 205 >SCHED&#0095;OTHER</I
 206 ></SPAN
 207 > is
 208           equivalent to <SPAN
 209 CLASS="emphasis"
 210 ><I
 211 CLASS="EMPHASIS"
 212 >SCHED&#0095;RR</I
 213 ></SPAN
 214 >.
 215           </P
 216 ></LI
 217 ><LI
 218 ><P
 219 >         Only <SPAN
 220 CLASS="emphasis"
 221 ><I
 222 CLASS="EMPHASIS"
 223 >PTHREAD&#0095;SCOPE&#0095;SYSTEM</I
 224 ></SPAN
 225 >
 226           is supported as a
 227           <SPAN
 228 CLASS="strong"
 229 ><B
 230 CLASS="EMPHASIS"
 231 >contentionscope</B
 232 ></SPAN
 233 >
 234           attribute.
 235           </P
 236 ></LI
 237 ><LI
 238 ><P
 239 >         The default thread scheduling attributes are:
 240           <TABLE
 241 BORDER="5"
 242 BGCOLOR="#E0E0F0"
 243 WIDTH="70%"
 244 ><TR
 245 ><TD
 246 ><PRE
 247 CLASS="SCREEN"
 248 >         contentionscope          PTHREAD&#0095;SCOPE&#0095;SYSTEM
 249           inheritsched             PTHREAD&#0095;INHERIT&#0095;SCHED
 250           schedpolicy              SCHED&#0095;OTHER
 251           schedparam.sched         0
 252           </PRE
 253 ></TD
 254 ></TR
 255 ></TABLE
 256 >
 257           </P
 258 ></LI
 259 ><LI
 260 ><P
 261 >         Mutex priority inversion protection is controlled by a
 262           number of kernel configuration options.
 263           If CYGSEM&#0095;KERNEL&#0095;SYNCH&#0095;MUTEX&#0095;PRIORITY&#0095;INVERSION&#0095;PROTOCOL&#0095;INHERIT
 264           is defined then
 265           &#0123;&#0095;POSIX&#0095;THREAD&#0095;PRIO&#0095;INHERIT&#0125;
 266           will be defined and PTHREAD&#0095;PRIO&#0095;INHERIT may
 267           be set as the protocol in a
 268           <SPAN
 269 CLASS="emphasis"
 270 ><I
 271 CLASS="EMPHASIS"
 272 >pthread&#0095;mutexattr&#0095;t</I
 273 ></SPAN
 274 >
 275           object.
 276           If CYGSEM&#0095;KERNEL&#0095;SYNCH&#0095;MUTEX&#0095;PRIORITY&#0095;INVERSION&#0095;PROTOCOL&#0095;CEILING
 277           is defined then
 278           &#0123;&#0095;POSIX&#0095;THREAD&#0095;PRIO&#0095;PROTECT&#0125;
 279           will be defined and PTHREAD&#0095;PRIO&#0095;PROTECT may
 280           be set as the protocol in a
 281           <SPAN
 282 CLASS="emphasis"
 283 ><I
 284 CLASS="EMPHASIS"
 285 >pthread&#0095;mutexattr&#0095;t</I
 286 ></SPAN
 287 > object.
 288           </P
 289 ></LI
 290 ><LI
 291 ><P
 292 >         The default attribute values set by
 293           <SPAN
 294 CLASS="emphasis"
 295 ><I
 296 CLASS="EMPHASIS"
 297 >pthread&#0095;mutexattr&#0095;init()</I
 298 ></SPAN
 299 >
 300           is to set the protocol attribute to
 301           PTHREAD&#0095;PRIO&#0095;NONE and the prioceiling
 302           attribute to zero.
 303           </P
 304 ></LI
 305 ></UL
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