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  75 >SDL_SemPost</H1
  76 ><DIV
  77 CLASS="REFNAMEDIV"
  78 ><A
  79 NAME="AEN8170"
  80 ></A
  81 ><H2
  82 >Name</H2
  83 >SDL_SemPost&nbsp;--&nbsp;Unlock a semaphore.</DIV
  84 ><DIV
  85 CLASS="REFSYNOPSISDIV"
  86 ><A
  87 NAME="AEN8173"
  88 ></A
  89 ><H2
  90 >Synopsis</H2
  91 ><DIV
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  94 NAME="AEN8174"
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  96 ><P
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  98 ><PRE
  99 CLASS="FUNCSYNOPSISINFO"
 100 >#include "SDL.h"
 101 #include "SDL_thread.h"</PRE
 102 ><P
 103 ><CODE
 104 ><CODE
 105 CLASS="FUNCDEF"
 106 >int <B
 107 CLASS="FSFUNC"
 108 >SDL_SemPost</B
 109 ></CODE
 110 >(SDL_sem *sem);</CODE
 111 ></P
 112 ><P
 113 ></P
 114 ></DIV
 115 ></DIV
 116 ><DIV
 117 CLASS="REFSECT1"
 118 ><A
 119 NAME="AEN8180"
 120 ></A
 121 ><H2
 122 >Description</H2
 123 ><P
 124 ><TT
 125 CLASS="FUNCTION"
 126 >SDL_SemPost</TT
 127 > unlocks the semaphore pointed to by
 128 <TT
 129 CLASS="PARAMETER"
 130 ><I
 131 >sem</I
 132 ></TT
 133 > and atomically increments the semaphores value.
 134 Threads that were blocking on the semaphore may be scheduled after this call
 135 succeeds.</P
 136 ><P
 137 ><TT
 138 CLASS="FUNCTION"
 139 >SDL_SemPost</TT
 140 > should be called after a semaphore is locked by a successful call to
 141 <A
 142 HREF="sdlsemwait.html"
 143 >SDL_SemWait</A
 144 >,
 145 <A
 146 HREF="sdlsemtrywait.html"
 147 >SDL_SemTryWait</A
 148 > or
 149 <A
 150 HREF="sdlsemwaittimeout.html"
 151 >SDL_SemWaitTimeout</A
 152 >.</P
 153 ></DIV
 154 ><DIV
 155 CLASS="REFSECT1"
 156 ><A
 157 NAME="AEN8190"
 158 ></A
 159 ><H2
 160 >Return Value</H2
 161 ><P
 162 >Returns <SPAN
 163 CLASS="RETURNVALUE"
 164 >0</SPAN
 165 > if successful or
 166 <SPAN
 167 CLASS="RETURNVALUE"
 168 >-1</SPAN
 169 > if there was an error (leaving the semaphore unchanged).</P
 170 ></DIV
 171 ><DIV
 172 CLASS="REFSECT1"
 173 ><A
 174 NAME="AEN8195"
 175 ></A
 176 ><H2
 177 >Examples</H2
 178 ><P
 179 ><PRE
 180 CLASS="PROGRAMLISTING"
 181 >SDL_SemPost(my_sem);</PRE
 182 ></P
 183 ></DIV
 184 ><DIV
 185 CLASS="REFSECT1"
 186 ><A
 187 NAME="AEN8199"
 188 ></A
 189 ><H2
 190 >See Also</H2
 191 ><P
 192 ><A
 193 HREF="sdlcreatesemaphore.html"
 194 ><TT
 195 CLASS="FUNCTION"
 196 >SDL_CreateSemaphore</TT
 197 ></A
 198 >,
 199 <A
 200 HREF="sdldestroysemaphore.html"
 201 ><TT
 202 CLASS="FUNCTION"
 203 >SDL_DestroySemaphore</TT
 204 ></A
 205 >,
 206 <A
 207 HREF="sdlsemwait.html"
 208 ><TT
 209 CLASS="FUNCTION"
 210 >SDL_SemWait</TT
 211 ></A
 212 >,
 213 <A
 214 HREF="sdlsemtrywait.html"
 215 ><TT
 216 CLASS="FUNCTION"
 217 >SDL_SemTryWait</TT
 218 ></A
 219 >,
 220 <A
 221 HREF="sdlsemwaittimeout.html"
 222 ><TT
 223 CLASS="FUNCTION"
 224 >SDL_SemWaitTimeout</TT
 225 ></A
 226 >,
 227 <A
 228 HREF="sdlsemvalue.html"
 229 ><TT
 230 CLASS="FUNCTION"
 231 >SDL_SemValue</TT
 232 ></A
 233 ></P
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