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1 <HTML |
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2 ><HEAD |
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3 ><TITLE |
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4 >SDL_SemPost</TITLE |
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16 TITLE="SDL_SemWaitTimeout" |
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19 TITLE="SDL_SemValue" |
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20 HREF="sdlsemvalue.html"></HEAD |
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35 CELLSPACING="0" |
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36 ><TR |
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37 ><TH |
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38 COLSPAN="3" |
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39 ALIGN="center" |
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40 >SDL Library Documentation</TH |
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41 ></TR |
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42 ><TR |
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43 ><TD |
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44 WIDTH="10%" |
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45 ALIGN="left" |
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46 VALIGN="bottom" |
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47 ><A |
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48 HREF="sdlsemwaittimeout.html" |
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49 ACCESSKEY="P" |
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50 >Prev</A |
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51 ></TD |
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52 ><TD |
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53 WIDTH="80%" |
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54 ALIGN="center" |
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55 VALIGN="bottom" |
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57 ><TD |
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58 WIDTH="10%" |
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59 ALIGN="right" |
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60 VALIGN="bottom" |
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61 ><A |
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62 HREF="sdlsemvalue.html" |
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63 ACCESSKEY="N" |
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64 >Next</A |
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65 ></TD |
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66 ></TR |
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67 ></TABLE |
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68 ><HR |
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69 ALIGN="LEFT" |
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70 WIDTH="100%"></DIV |
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71 ><H1 |
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72 ><A |
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73 NAME="SDLSEMPOST" |
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74 ></A |
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75 >SDL_SemPost</H1 |
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76 ><DIV |
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77 CLASS="REFNAMEDIV" |
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78 ><A |
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79 NAME="AEN8170" |
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80 ></A |
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81 ><H2 |
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82 >Name</H2 |
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83 >SDL_SemPost -- Unlock a semaphore.</DIV |
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84 ><DIV |
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85 CLASS="REFSYNOPSISDIV" |
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86 ><A |
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87 NAME="AEN8173" |
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88 ></A |
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89 ><H2 |
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90 >Synopsis</H2 |
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91 ><DIV |
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92 CLASS="FUNCSYNOPSIS" |
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93 ><A |
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94 NAME="AEN8174" |
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95 ></A |
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96 ><P |
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97 ></P |
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98 ><PRE |
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99 CLASS="FUNCSYNOPSISINFO" |
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100 >#include "SDL.h" |
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101 #include "SDL_thread.h"</PRE |
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102 ><P |
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103 ><CODE |
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104 ><CODE |
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105 CLASS="FUNCDEF" |
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106 >int <B |
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107 CLASS="FSFUNC" |
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108 >SDL_SemPost</B |
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109 ></CODE |
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110 >(SDL_sem *sem);</CODE |
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111 ></P |
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112 ><P |
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113 ></P |
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114 ></DIV |
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115 ></DIV |
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116 ><DIV |
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117 CLASS="REFSECT1" |
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118 ><A |
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119 NAME="AEN8180" |
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120 ></A |
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121 ><H2 |
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122 >Description</H2 |
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123 ><P |
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124 ><TT |
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125 CLASS="FUNCTION" |
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126 >SDL_SemPost</TT |
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127 > unlocks the semaphore pointed to by |
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128 <TT |
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129 CLASS="PARAMETER" |
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130 ><I |
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131 >sem</I |
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132 ></TT |
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133 > and atomically increments the semaphores value. |
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134 Threads that were blocking on the semaphore may be scheduled after this call |
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135 succeeds.</P |
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136 ><P |
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137 ><TT |
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138 CLASS="FUNCTION" |
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139 >SDL_SemPost</TT |
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140 > should be called after a semaphore is locked by a successful call to |
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141 <A |
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142 HREF="sdlsemwait.html" |
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143 >SDL_SemWait</A |
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144 >, |
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145 <A |
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146 HREF="sdlsemtrywait.html" |
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147 >SDL_SemTryWait</A |
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148 > or |
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149 <A |
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150 HREF="sdlsemwaittimeout.html" |
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151 >SDL_SemWaitTimeout</A |
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152 >.</P |
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153 ></DIV |
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154 ><DIV |
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155 CLASS="REFSECT1" |
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156 ><A |
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157 NAME="AEN8190" |
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158 ></A |
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159 ><H2 |
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160 >Return Value</H2 |
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161 ><P |
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162 >Returns <SPAN |
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163 CLASS="RETURNVALUE" |
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164 >0</SPAN |
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165 > if successful or |
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166 <SPAN |
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167 CLASS="RETURNVALUE" |
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168 >-1</SPAN |
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169 > if there was an error (leaving the semaphore unchanged).</P |
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170 ></DIV |
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171 ><DIV |
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172 CLASS="REFSECT1" |
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173 ><A |
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174 NAME="AEN8195" |
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175 ></A |
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176 ><H2 |
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177 >Examples</H2 |
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178 ><P |
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179 ><PRE |
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180 CLASS="PROGRAMLISTING" |
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181 >SDL_SemPost(my_sem);</PRE |
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182 ></P |
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183 ></DIV |
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184 ><DIV |
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185 CLASS="REFSECT1" |
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186 ><A |
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187 NAME="AEN8199" |
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188 ></A |
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189 ><H2 |
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190 >See Also</H2 |
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191 ><P |
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192 ><A |
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193 HREF="sdlcreatesemaphore.html" |
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194 ><TT |
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195 CLASS="FUNCTION" |
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196 >SDL_CreateSemaphore</TT |
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197 ></A |
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198 >, |
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199 <A |
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200 HREF="sdldestroysemaphore.html" |
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201 ><TT |
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202 CLASS="FUNCTION" |
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203 >SDL_DestroySemaphore</TT |
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204 ></A |
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205 >, |
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206 <A |
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207 HREF="sdlsemwait.html" |
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208 ><TT |
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209 CLASS="FUNCTION" |
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210 >SDL_SemWait</TT |
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211 ></A |
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212 >, |
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213 <A |
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214 HREF="sdlsemtrywait.html" |
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215 ><TT |
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216 CLASS="FUNCTION" |
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217 >SDL_SemTryWait</TT |
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218 ></A |
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219 >, |
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220 <A |
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221 HREF="sdlsemwaittimeout.html" |
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222 ><TT |
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223 CLASS="FUNCTION" |
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224 >SDL_SemWaitTimeout</TT |
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225 ></A |
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226 >, |
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227 <A |
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228 HREF="sdlsemvalue.html" |
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229 ><TT |
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230 CLASS="FUNCTION" |
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231 >SDL_SemValue</TT |
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232 ></A |
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233 ></P |
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234 ></DIV |
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249 VALIGN="top" |
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251 HREF="sdlsemwaittimeout.html" |
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253 >Prev</A |
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269 HREF="sdlsemvalue.html" |
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271 >Next</A |
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274 ><TR |
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277 ALIGN="left" |
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278 VALIGN="top" |
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279 >SDL_SemWaitTimeout</TD |
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280 ><TD |
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281 WIDTH="34%" |
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293 >SDL_SemValue</TD |
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299 > |