1 | .. comment SPDX-License-Identifier: CC-BY-SA-4.0 |
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2 | |
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3 | .. COMMENT: COPYRIGHT (c) 1988-2002. |
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4 | .. COMMENT: On-Line Applications Research Corporation (OAR). |
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5 | .. COMMENT: All rights reserved. |
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6 | |
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7 | Thread Manager |
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8 | ############## |
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9 | |
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10 | Introduction |
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11 | ============ |
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12 | |
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13 | The thread manager implements the functionality required of the thread manager |
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14 | as defined by POSIX 1003.1b. This standard requires that a compliant operating |
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15 | system provide the facilties to manage multiple threads of control and defines |
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16 | the API that must be provided. |
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17 | |
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18 | The services provided by the thread manager are: |
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19 | |
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20 | - pthread_attr_init_ - Initialize a Thread Attribute Set |
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21 | |
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22 | - pthread_attr_destroy_ - Destroy a Thread Attribute Set |
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23 | |
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24 | - pthread_attr_setdetachstate_ - Set Detach State |
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25 | |
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26 | - pthread_attr_getdetachstate_ - Get Detach State |
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27 | |
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28 | - pthread_attr_setstacksize_ - Set Thread Stack Size |
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29 | |
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30 | - pthread_attr_getstacksize_ - Get Thread Stack Size |
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31 | |
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32 | - pthread_attr_setstackaddr_ - Set Thread Stack Address |
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33 | |
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34 | - pthread_attr_getstackaddr_ - Get Thread Stack Address |
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35 | |
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36 | - pthread_attr_setscope_ - Set Thread Scheduling Scope |
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37 | |
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38 | - pthread_attr_getscope_ - Get Thread Scheduling Scope |
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39 | |
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40 | - pthread_attr_setinheritsched_ - Set Inherit Scheduler Flag |
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41 | |
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42 | - pthread_attr_getinheritsched_ - Get Inherit Scheduler Flag |
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43 | |
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44 | - pthread_attr_setschedpolicy_ - Set Scheduling Policy |
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45 | |
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46 | - pthread_attr_getschedpolicy_ - Get Scheduling Policy |
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47 | |
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48 | - pthread_attr_setschedparam_ - Set Scheduling Parameters |
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49 | |
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50 | - pthread_attr_getschedparam_ - Get Scheduling Parameters |
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51 | |
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52 | - pthread_attr_getaffinity_np_ - Get Thread Affinity Attribute |
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53 | |
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54 | - pthread_attr_setaffinity_np_ - Set Thread Affinity Attribute |
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55 | |
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56 | - pthread_create_ - Create a Thread |
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57 | |
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58 | - pthread_exit_ - Terminate the Current Thread |
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59 | |
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60 | - pthread_detach_ - Detach a Thread |
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61 | |
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62 | - pthread_getattr_np_ - Get Thread Attributes |
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63 | |
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64 | - pthread_join_ - Wait for Thread Termination |
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65 | |
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66 | - pthread_self_ - Get Thread ID |
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67 | |
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68 | - pthread_equal_ - Compare Thread IDs |
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69 | |
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70 | - pthread_once_ - Dynamic Package Initialization |
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71 | |
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72 | - pthread_setschedparam_ - Set Thread Scheduling Parameters |
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73 | |
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74 | - pthread_getschedparam_ - Get Thread Scheduling Parameters |
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75 | |
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76 | - pthread_getaffinity_np_ - Get Thread Affinity |
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77 | |
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78 | - pthread_setaffinity_np_ - Set Thread Affinity |
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79 | |
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80 | Background |
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81 | ========== |
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82 | |
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83 | Thread Attributes |
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84 | ----------------- |
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85 | |
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86 | Thread attributes are utilized only at thread creation time. A thread attribute |
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87 | structure may be initialized and passed as an argument to the |
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88 | ``pthread_create`` routine. |
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89 | |
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90 | *stack address* |
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91 | is the address of the optionally user specified stack area for this thread. |
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92 | If this value is NULL, then RTEMS allocates the memory for the thread stack |
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93 | from the RTEMS Workspace Area. Otherwise, this is the user specified |
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94 | address for the memory to be used for the thread's stack. Each thread must |
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95 | have a distinct stack area. Each processor family has different alignment |
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96 | rules which should be followed. |
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97 | |
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98 | *stack size* |
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99 | is the minimum desired size for this thread's stack area. If the size of |
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100 | this area as specified by the stack size attribute is smaller than the |
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101 | minimum for this processor family and the stack is not user specified, then |
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102 | RTEMS will automatically allocate a stack of the minimum size for this |
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103 | processor family. |
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104 | |
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105 | *contention scope* |
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106 | specifies the scheduling contention scope. RTEMS only supports the |
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107 | PTHREAD_SCOPE_PROCESS scheduling contention scope. |
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108 | |
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109 | *scheduling inheritance* |
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110 | specifies whether a user specified or the scheduling policy and parameters |
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111 | of the currently executing thread are to be used. When this is |
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112 | PTHREAD_INHERIT_SCHED, then the scheduling policy and parameters of the |
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113 | currently executing thread are inherited by the newly created thread. |
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114 | |
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115 | *scheduling policy and parameters* |
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116 | specify the manner in which the thread will contend for the processor. The |
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117 | scheduling parameters are interpreted based on the specified policy. All |
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118 | policies utilize the thread priority parameter. |
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119 | |
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120 | Operations |
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121 | ========== |
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122 | |
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123 | There is currently no text in this section. |
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124 | |
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125 | Services |
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126 | ======== |
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127 | |
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128 | This section details the thread manager's services. A subsection is dedicated |
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129 | to each of this manager's services and describes the calling sequence, related |
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130 | constants, usage, and status codes. |
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131 | |
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132 | .. _pthread_attr_init: |
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133 | |
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134 | pthread_attr_init - Initialize a Thread Attribute Set |
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135 | ----------------------------------------------------- |
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136 | .. index:: pthread_attr_init |
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137 | .. index:: initialize a thread attribute set |
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138 | |
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139 | **CALLING SEQUENCE:** |
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140 | |
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141 | .. code-block:: c |
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142 | |
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143 | #include <pthread.h> |
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144 | int pthread_attr_init( |
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145 | pthread_attr_t *attr |
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146 | ); |
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147 | |
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148 | **STATUS CODES:** |
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149 | |
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150 | .. list-table:: |
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151 | :class: rtems-table |
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152 | |
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153 | * - ``EINVAL`` |
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154 | - The attribute pointer argument is invalid. |
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155 | |
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156 | **DESCRIPTION:** |
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157 | |
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158 | The ``pthread_attr_init`` routine initializes the thread attributes object |
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159 | specified by ``attr`` with the default value for all of the individual |
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160 | attributes. |
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161 | |
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162 | **NOTES:** |
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163 | |
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164 | The settings in the default attributes are implementation defined. For RTEMS, |
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165 | the default attributes are as follows: |
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166 | |
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167 | .. list-table:: |
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168 | :class: rtems-table |
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169 | |
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170 | * - *stackadr* |
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171 | - is not set to indicate that RTEMS is to allocate the stack memory. |
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172 | * - *stacksize* |
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173 | - is set to ``PTHREAD_MINIMUM_STACK_SIZE``. |
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174 | * - *contentionscope* |
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175 | - is set to ``PTHREAD_SCOPE_PROCESS``. |
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176 | * - *inheritsched* |
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177 | - is set to ``PTHREAD_INHERIT_SCHED`` to indicate that the created thread |
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178 | inherits its scheduling attributes from its parent. |
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179 | * - detachstate |
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180 | - is set to ``PTHREAD_CREATE_JOINABLE``. |
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181 | |
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182 | .. _pthread_attr_destroy: |
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183 | |
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184 | pthread_attr_destroy - Destroy a Thread Attribute Set |
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185 | ----------------------------------------------------- |
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186 | .. index:: pthread_attr_destroy |
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187 | .. index:: destroy a thread attribute set |
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188 | |
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189 | **CALLING SEQUENCE:** |
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190 | |
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191 | .. code-block:: c |
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192 | |
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193 | #include <pthread.h> |
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194 | int pthread_attr_destroy( |
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195 | pthread_attr_t *attr |
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196 | ); |
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197 | |
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198 | **STATUS CODES:** |
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199 | |
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200 | .. list-table:: |
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201 | :class: rtems-table |
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202 | |
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203 | * - ``EINVAL`` |
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204 | - The attribute pointer argument is invalid. |
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205 | * - ``EINVAL`` |
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206 | - The attribute set is not initialized. |
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207 | |
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208 | **DESCRIPTION:** |
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209 | |
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210 | The ``pthread_attr_destroy`` routine is used to destroy a thread attributes |
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211 | object. The behavior of using an attributes object after it is destroyed is |
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212 | implementation dependent. |
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213 | |
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214 | **NOTES:** |
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215 | |
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216 | NONE |
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217 | |
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218 | .. _pthread_attr_setdetachstate: |
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219 | |
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220 | pthread_attr_setdetachstate - Set Detach State |
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221 | ---------------------------------------------- |
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222 | .. index:: pthread_attr_setdetachstate |
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223 | .. index:: set detach state |
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224 | |
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225 | **CALLING SEQUENCE:** |
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226 | |
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227 | .. code-block:: c |
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228 | |
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229 | #include <pthread.h> |
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230 | int pthread_attr_setdetachstate( |
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231 | pthread_attr_t *attr, |
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232 | int detachstate |
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233 | ); |
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234 | |
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235 | **STATUS CODES:** |
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236 | |
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237 | .. list-table:: |
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238 | :class: rtems-table |
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239 | |
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240 | * - ``EINVAL`` |
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241 | - The attribute pointer argument is invalid. |
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242 | * - ``EINVAL`` |
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243 | - The attribute set is not initialized. |
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244 | * - ``EINVAL`` |
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245 | - The detachstate argument is invalid. |
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246 | |
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247 | **DESCRIPTION:** |
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248 | |
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249 | The ``pthread_attr_setdetachstate`` routine is used to value of the |
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250 | ``detachstate`` attribute. This attribute controls whether the thread is |
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251 | created in a detached state. |
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252 | |
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253 | The ``detachstate`` can be either ``PTHREAD_CREATE_DETACHED`` or |
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254 | ``PTHREAD_CREATE_JOINABLE``. The default value for all threads is |
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255 | ``PTHREAD_CREATE_JOINABLE``. |
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256 | |
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257 | **NOTES:** |
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258 | |
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259 | If a thread is in a detached state, then the use of the ID with the |
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260 | ``pthread_detach`` or ``pthread_join`` routines is an error. |
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261 | |
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262 | .. _pthread_attr_getdetachstate: |
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263 | |
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264 | pthread_attr_getdetachstate - Get Detach State |
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265 | ---------------------------------------------- |
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266 | .. index:: pthread_attr_getdetachstate |
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267 | .. index:: get detach state |
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268 | |
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269 | **CALLING SEQUENCE:** |
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270 | |
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271 | .. code-block:: c |
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272 | |
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273 | #include <pthread.h> |
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274 | int pthread_attr_getdetachstate( |
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275 | const pthread_attr_t *attr, |
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276 | int *detachstate |
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277 | ); |
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278 | |
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279 | **STATUS CODES:** |
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280 | |
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281 | .. list-table:: |
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282 | :class: rtems-table |
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283 | |
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284 | * - ``EINVAL`` |
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285 | - The attribute pointer argument is invalid. |
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286 | * - ``EINVAL`` |
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287 | - The attribute set is not initialized. |
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288 | * - ``EINVAL`` |
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289 | - The detatchstate pointer argument is invalid. |
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290 | |
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291 | **DESCRIPTION:** |
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292 | |
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293 | The ``pthread_attr_getdetachstate`` routine is used to obtain the current value |
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294 | of the ``detachstate`` attribute as specified by the ``attr`` thread attribute |
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295 | object. |
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296 | |
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297 | **NOTES:** |
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298 | |
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299 | NONE |
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300 | |
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301 | .. _pthread_attr_setstacksize: |
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302 | |
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303 | pthread_attr_setstacksize - Set Thread Stack Size |
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304 | ------------------------------------------------- |
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305 | .. index:: pthread_attr_setstacksize |
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306 | .. index:: set thread stack size |
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307 | |
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308 | **CALLING SEQUENCE:** |
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309 | |
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310 | .. code-block:: c |
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311 | |
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312 | #include <pthread.h> |
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313 | int pthread_attr_setstacksize( |
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314 | pthread_attr_t *attr, |
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315 | size_t stacksize |
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316 | ); |
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317 | |
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318 | **STATUS CODES:** |
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319 | |
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320 | .. list-table:: |
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321 | :class: rtems-table |
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322 | |
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323 | * - ``EINVAL`` |
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324 | - The attribute pointer argument is invalid. |
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325 | * - ``EINVAL`` |
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326 | - The attribute set is not initialized. |
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327 | |
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328 | **DESCRIPTION:** |
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329 | |
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330 | The ``pthread_attr_setstacksize`` routine is used to set the ``stacksize`` |
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331 | attribute in the ``attr`` thread attribute object. |
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332 | |
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333 | **NOTES:** |
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334 | |
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335 | As required by POSIX, RTEMS defines the feature symbol |
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336 | ``_POSIX_THREAD_ATTR_STACKSIZE`` to indicate that this routine is supported. |
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337 | |
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338 | If the specified stacksize is below the minimum required for this CPU |
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339 | (``PTHREAD_STACK_MIN``, then the stacksize will be set to the minimum for this |
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340 | CPU. |
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341 | |
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342 | .. _pthread_attr_getstacksize: |
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343 | |
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344 | pthread_attr_getstacksize - Get Thread Stack Size |
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345 | ------------------------------------------------- |
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346 | .. index:: pthread_attr_getstacksize |
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347 | .. index:: get thread stack size |
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348 | |
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349 | **CALLING SEQUENCE:** |
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350 | |
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351 | .. code-block:: c |
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352 | |
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353 | #include <pthread.h> |
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354 | int pthread_attr_getstacksize( |
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355 | const pthread_attr_t *attr, |
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356 | size_t *stacksize |
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357 | ); |
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358 | |
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359 | **STATUS CODES:** |
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360 | |
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361 | .. list-table:: |
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362 | :class: rtems-table |
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363 | |
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364 | * - ``EINVAL`` |
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365 | - The attribute pointer argument is invalid. |
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366 | * - ``EINVAL`` |
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367 | - The attribute set is not initialized. |
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368 | * - ``EINVAL`` |
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369 | - The stacksize pointer argument is invalid. |
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370 | |
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371 | **DESCRIPTION:** |
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372 | |
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373 | The ``pthread_attr_getstacksize`` routine is used to obtain the ``stacksize`` |
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374 | attribute in the ``attr`` thread attribute object. |
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375 | |
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376 | **NOTES:** |
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377 | |
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378 | As required by POSIX, RTEMS defines the feature symbol |
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379 | ``_POSIX_THREAD_ATTR_STACKSIZE`` to indicate that this routine is supported. |
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380 | |
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381 | .. _pthread_attr_setstackaddr: |
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382 | |
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383 | pthread_attr_setstackaddr - Set Thread Stack Address |
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384 | ---------------------------------------------------- |
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385 | .. index:: pthread_attr_setstackaddr |
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386 | .. index:: set thread stack address |
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387 | |
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388 | **CALLING SEQUENCE:** |
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389 | |
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390 | .. code-block:: c |
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391 | |
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392 | #include <pthread.h> |
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393 | int pthread_attr_setstackaddr( |
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394 | pthread_attr_t *attr, |
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395 | void *stackaddr |
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396 | ); |
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397 | |
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398 | **STATUS CODES:** |
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399 | |
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400 | .. list-table:: |
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401 | :class: rtems-table |
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402 | |
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403 | * - ``EINVAL`` |
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404 | - The attribute pointer argument is invalid. |
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405 | * - ``EINVAL`` |
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406 | - The attribute set is not initialized. |
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407 | |
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408 | **DESCRIPTION:** |
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409 | |
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410 | The ``pthread_attr_setstackaddr`` routine is used to set the ``stackaddr`` |
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411 | attribute in the ``attr`` thread attribute object. |
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412 | |
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413 | **NOTES:** |
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414 | |
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415 | As required by POSIX, RTEMS defines the feature symbol |
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416 | ``_POSIX_THREAD_ATTR_STACKADDR`` to indicate that this routine is supported. |
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417 | |
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418 | It is imperative to the proper operation of the system that each thread have |
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419 | sufficient stack space. |
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420 | |
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421 | .. _pthread_attr_getstackaddr: |
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422 | |
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423 | pthread_attr_getstackaddr - Get Thread Stack Address |
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424 | ---------------------------------------------------- |
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425 | .. index:: pthread_attr_getstackaddr |
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426 | .. index:: get thread stack address |
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427 | |
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428 | **CALLING SEQUENCE:** |
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429 | |
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430 | .. code-block:: c |
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431 | |
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432 | #include <pthread.h> |
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433 | int pthread_attr_getstackaddr( |
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434 | const pthread_attr_t *attr, |
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435 | void **stackaddr |
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436 | ); |
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437 | |
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438 | **STATUS CODES:** |
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439 | |
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440 | .. list-table:: |
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441 | :class: rtems-table |
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442 | |
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443 | * - ``EINVAL`` |
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444 | - The attribute pointer argument is invalid. |
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445 | * - ``EINVAL`` |
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446 | - The attribute set is not initialized. |
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447 | * - ``EINVAL`` |
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448 | - The stackaddr pointer argument is invalid. |
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449 | |
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450 | **DESCRIPTION:** |
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451 | |
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452 | The ``pthread_attr_getstackaddr`` routine is used to obtain the ``stackaddr`` |
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453 | attribute in the ``attr`` thread attribute object. |
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454 | |
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455 | **NOTES:** |
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456 | |
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457 | As required by POSIX, RTEMS defines the feature symbol |
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458 | ``_POSIX_THREAD_ATTR_STACKADDR`` to indicate that this routine is supported. |
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459 | |
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460 | .. _pthread_attr_setscope: |
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461 | |
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462 | pthread_attr_setscope - Set Thread Scheduling Scope |
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463 | --------------------------------------------------- |
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464 | .. index:: pthread_attr_setscope |
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465 | .. index:: set thread scheduling scope |
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466 | |
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467 | **CALLING SEQUENCE:** |
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468 | |
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469 | .. code-block:: c |
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470 | |
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471 | #include <pthread.h> |
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472 | int pthread_attr_setscope( |
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473 | pthread_attr_t *attr, |
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474 | int contentionscope |
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475 | ); |
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476 | |
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477 | **STATUS CODES:** |
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478 | |
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479 | .. list-table:: |
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480 | :class: rtems-table |
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481 | |
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482 | * - ``EINVAL`` |
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483 | - The attribute pointer argument is invalid. |
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484 | * - ``EINVAL`` |
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485 | - The attribute set is not initialized. |
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486 | * - ``EINVAL`` |
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487 | - The contention scope specified is not valid. |
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488 | * - ``ENOTSUP`` |
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489 | - The contention scope specified (``PTHREAD_SCOPE_SYSTEM``) is not supported. |
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490 | |
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491 | **DESCRIPTION:** |
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492 | |
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493 | The ``pthread_attr_setscope`` routine is used to set the contention scope field |
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494 | in the thread attribute object ``attr`` to the value specified by |
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495 | ``contentionscope``. |
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496 | |
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497 | The ``contentionscope`` must be either ``PTHREAD_SCOPE_SYSTEM`` to indicate |
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498 | that the thread is to be within system scheduling contention or |
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499 | ``PTHREAD_SCOPE_PROCESS`` indicating that the thread is to be within the |
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500 | process scheduling contention scope. |
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501 | |
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502 | **NOTES:** |
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503 | |
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504 | As required by POSIX, RTEMS defines the feature symbol |
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505 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
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506 | to which this routine belongs is supported. |
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507 | |
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508 | .. _pthread_attr_getscope: |
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509 | |
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510 | pthread_attr_getscope - Get Thread Scheduling Scope |
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511 | --------------------------------------------------- |
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512 | .. index:: pthread_attr_getscope |
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513 | .. index:: get thread scheduling scope |
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514 | |
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515 | **CALLING SEQUENCE:** |
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516 | |
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517 | .. code-block:: c |
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518 | |
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519 | #include <pthread.h> |
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520 | int pthread_attr_getscope( |
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521 | const pthread_attr_t *attr, |
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522 | int *contentionscope |
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523 | ); |
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524 | |
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525 | **STATUS CODES:** |
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526 | |
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527 | .. list-table:: |
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528 | :class: rtems-table |
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529 | |
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530 | * - ``EINVAL`` |
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531 | - The attribute pointer argument is invalid. |
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532 | * - ``EINVAL`` |
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533 | - The attribute set is not initialized. |
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534 | * - ``EINVAL`` |
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535 | - The contentionscope pointer argument is invalid. |
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536 | |
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537 | **DESCRIPTION:** |
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538 | |
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539 | The ``pthread_attr_getscope`` routine is used to obtain the value of the |
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540 | contention scope field in the thread attributes object ``attr``. The current |
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541 | value is returned in ``contentionscope``. |
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542 | |
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543 | **NOTES:** |
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544 | |
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545 | As required by POSIX, RTEMS defines the feature symbol |
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546 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
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547 | to which this routine belongs is supported. |
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548 | |
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549 | .. _pthread_attr_setinheritsched: |
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550 | |
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551 | pthread_attr_setinheritsched - Set Inherit Scheduler Flag |
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552 | --------------------------------------------------------- |
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553 | .. index:: pthread_attr_setinheritsched |
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554 | .. index:: set inherit scheduler flag |
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555 | |
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556 | **CALLING SEQUENCE:** |
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557 | |
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558 | .. code-block:: c |
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559 | |
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560 | #include <pthread.h> |
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561 | int pthread_attr_setinheritsched( |
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562 | pthread_attr_t *attr, |
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563 | int inheritsched |
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564 | ); |
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565 | |
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566 | **STATUS CODES:** |
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567 | |
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568 | .. list-table:: |
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569 | :class: rtems-table |
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570 | |
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571 | * - ``EINVAL`` |
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572 | - The attribute pointer argument is invalid. |
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573 | * - ``EINVAL`` |
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574 | - The attribute set is not initialized. |
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575 | * - ``EINVAL`` |
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576 | - The specified scheduler inheritance argument is invalid. |
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577 | |
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578 | **DESCRIPTION:** |
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579 | |
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580 | The ``pthread_attr_setinheritsched`` routine is used to set the inherit |
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581 | scheduler field in the thread attribute object ``attr`` to the value specified |
---|
582 | by ``inheritsched``. |
---|
583 | |
---|
584 | The ``contentionscope`` must be either ``PTHREAD_INHERIT_SCHED`` to indicate |
---|
585 | that the thread is to inherit the scheduling policy and parameters fromthe |
---|
586 | creating thread, or ``PTHREAD_EXPLICIT_SCHED`` to indicate that the scheduling |
---|
587 | policy and parameters for this thread are to be set from the corresponding |
---|
588 | values in the attributes object. If ``contentionscope`` is |
---|
589 | ``PTHREAD_INHERIT_SCHED``, then the scheduling attributes in the ``attr`` |
---|
590 | structure will be ignored at thread creation time. |
---|
591 | |
---|
592 | **NOTES:** |
---|
593 | |
---|
594 | As required by POSIX, RTEMS defines the feature symbol |
---|
595 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
596 | to which this routine belongs is supported. |
---|
597 | |
---|
598 | .. _pthread_attr_getinheritsched: |
---|
599 | |
---|
600 | pthread_attr_getinheritsched - Get Inherit Scheduler Flag |
---|
601 | --------------------------------------------------------- |
---|
602 | .. index:: pthread_attr_getinheritsched |
---|
603 | .. index:: get inherit scheduler flag |
---|
604 | |
---|
605 | **CALLING SEQUENCE:** |
---|
606 | |
---|
607 | .. code-block:: c |
---|
608 | |
---|
609 | #include <pthread.h> |
---|
610 | int pthread_attr_getinheritsched( |
---|
611 | const pthread_attr_t *attr, |
---|
612 | int *inheritsched |
---|
613 | ); |
---|
614 | |
---|
615 | **STATUS CODES:** |
---|
616 | |
---|
617 | .. list-table:: |
---|
618 | :class: rtems-table |
---|
619 | |
---|
620 | * - ``EINVAL`` |
---|
621 | - The attribute pointer argument is invalid. |
---|
622 | * - ``EINVAL`` |
---|
623 | - The attribute set is not initialized. |
---|
624 | * - ``EINVAL`` |
---|
625 | - The inheritsched pointer argument is invalid. |
---|
626 | |
---|
627 | **DESCRIPTION:** |
---|
628 | |
---|
629 | The ``pthread_attr_getinheritsched`` routine is used to object the current |
---|
630 | value of the inherit scheduler field in the thread attribute object ``attr``. |
---|
631 | |
---|
632 | **NOTES:** |
---|
633 | |
---|
634 | As required by POSIX, RTEMS defines the feature symbol |
---|
635 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
636 | to which this routine belongs is supported. |
---|
637 | |
---|
638 | .. _pthread_attr_setschedpolicy: |
---|
639 | |
---|
640 | pthread_attr_setschedpolicy - Set Scheduling Policy |
---|
641 | --------------------------------------------------- |
---|
642 | .. index:: pthread_attr_setschedpolicy |
---|
643 | .. index:: set scheduling policy |
---|
644 | |
---|
645 | **CALLING SEQUENCE:** |
---|
646 | |
---|
647 | .. code-block:: c |
---|
648 | |
---|
649 | #include <pthread.h> |
---|
650 | int pthread_attr_setschedpolicy( |
---|
651 | pthread_attr_t *attr, |
---|
652 | int policy |
---|
653 | ); |
---|
654 | |
---|
655 | **STATUS CODES:** |
---|
656 | |
---|
657 | .. list-table:: |
---|
658 | :class: rtems-table |
---|
659 | |
---|
660 | * - ``EINVAL`` |
---|
661 | - The attribute pointer argument is invalid. |
---|
662 | * - ``EINVAL`` |
---|
663 | - The attribute set is not initialized. |
---|
664 | * - ``ENOTSUP`` |
---|
665 | - The specified scheduler policy argument is invalid. |
---|
666 | |
---|
667 | **DESCRIPTION:** |
---|
668 | |
---|
669 | The ``pthread_attr_setschedpolicy`` routine is used to set the scheduler policy |
---|
670 | field in the thread attribute object ``attr`` to the value specified by |
---|
671 | ``policy``. |
---|
672 | |
---|
673 | Scheduling policies may be one of the following: |
---|
674 | |
---|
675 | - ``SCHED_DEFAULT`` |
---|
676 | |
---|
677 | - ``SCHED_FIFO`` |
---|
678 | |
---|
679 | - ``SCHED_RR`` |
---|
680 | |
---|
681 | - ``SCHED_SPORADIC`` |
---|
682 | |
---|
683 | - ``SCHED_OTHER`` |
---|
684 | |
---|
685 | The precise meaning of each of these is discussed elsewhere in this manual. |
---|
686 | |
---|
687 | **NOTES:** |
---|
688 | |
---|
689 | As required by POSIX, RTEMS defines the feature symbol |
---|
690 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
691 | to which this routine belongs is supported. |
---|
692 | |
---|
693 | .. _pthread_attr_getschedpolicy: |
---|
694 | |
---|
695 | pthread_attr_getschedpolicy - Get Scheduling Policy |
---|
696 | --------------------------------------------------- |
---|
697 | .. index:: pthread_attr_getschedpolicy |
---|
698 | .. index:: get scheduling policy |
---|
699 | |
---|
700 | **CALLING SEQUENCE:** |
---|
701 | |
---|
702 | .. code-block:: c |
---|
703 | |
---|
704 | #include <pthread.h> |
---|
705 | int pthread_attr_getschedpolicy( |
---|
706 | const pthread_attr_t *attr, |
---|
707 | int *policy |
---|
708 | ); |
---|
709 | |
---|
710 | **STATUS CODES:** |
---|
711 | |
---|
712 | .. list-table:: |
---|
713 | :class: rtems-table |
---|
714 | |
---|
715 | * - ``EINVAL`` |
---|
716 | - The attribute pointer argument is invalid. |
---|
717 | * - ``EINVAL`` |
---|
718 | - The attribute set is not initialized. |
---|
719 | * - ``EINVAL`` |
---|
720 | - The specified scheduler policy argument pointer is invalid. |
---|
721 | |
---|
722 | **DESCRIPTION:** |
---|
723 | |
---|
724 | The ``pthread_attr_getschedpolicy`` routine is used to obtain the scheduler |
---|
725 | policy field from the thread attribute object ``attr``. The value of this |
---|
726 | field is returned in ``policy``. |
---|
727 | |
---|
728 | **NOTES:** |
---|
729 | |
---|
730 | As required by POSIX, RTEMS defines the feature symbol |
---|
731 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
732 | to which this routine belongs is supported. |
---|
733 | |
---|
734 | .. _pthread_attr_setschedparam: |
---|
735 | |
---|
736 | pthread_attr_setschedparam - Set Scheduling Parameters |
---|
737 | ------------------------------------------------------ |
---|
738 | .. index:: pthread_attr_setschedparam |
---|
739 | .. index:: set scheduling parameters |
---|
740 | |
---|
741 | **CALLING SEQUENCE:** |
---|
742 | |
---|
743 | .. code-block:: c |
---|
744 | |
---|
745 | #include <pthread.h> |
---|
746 | int pthread_attr_setschedparam( |
---|
747 | pthread_attr_t *attr, |
---|
748 | const struct sched_param param |
---|
749 | ); |
---|
750 | |
---|
751 | **STATUS CODES:** |
---|
752 | |
---|
753 | .. list-table:: |
---|
754 | :class: rtems-table |
---|
755 | |
---|
756 | * - ``EINVAL`` |
---|
757 | - The attribute pointer argument is invalid. |
---|
758 | * - ``EINVAL`` |
---|
759 | - The attribute set is not initialized. |
---|
760 | * - ``EINVAL`` |
---|
761 | - The specified scheduler parameter argument is invalid. |
---|
762 | |
---|
763 | **DESCRIPTION:** |
---|
764 | |
---|
765 | The ``pthread_attr_setschedparam`` routine is used to set the scheduler |
---|
766 | parameters field in the thread attribute object ``attr`` to the value specified |
---|
767 | by ``param``. |
---|
768 | |
---|
769 | **NOTES:** |
---|
770 | |
---|
771 | As required by POSIX, RTEMS defines the feature symbol |
---|
772 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
773 | to which this routine belongs is supported. |
---|
774 | |
---|
775 | .. _pthread_attr_getschedparam: |
---|
776 | |
---|
777 | pthread_attr_getschedparam - Get Scheduling Parameters |
---|
778 | ------------------------------------------------------ |
---|
779 | .. index:: pthread_attr_getschedparam |
---|
780 | .. index:: get scheduling parameters |
---|
781 | |
---|
782 | **CALLING SEQUENCE:** |
---|
783 | |
---|
784 | .. code-block:: c |
---|
785 | |
---|
786 | #include <pthread.h> |
---|
787 | int pthread_attr_getschedparam( |
---|
788 | const pthread_attr_t *attr, |
---|
789 | struct sched_param *param |
---|
790 | ); |
---|
791 | |
---|
792 | **STATUS CODES:** |
---|
793 | |
---|
794 | .. list-table:: |
---|
795 | :class: rtems-table |
---|
796 | |
---|
797 | * - ``EINVAL`` |
---|
798 | - The attribute pointer argument is invalid. |
---|
799 | * - ``EINVAL`` |
---|
800 | - The attribute set is not initialized. |
---|
801 | * - ``EINVAL`` |
---|
802 | - The specified scheduler parameter argument pointer is invalid. |
---|
803 | |
---|
804 | **DESCRIPTION:** |
---|
805 | |
---|
806 | The ``pthread_attr_getschedparam`` routine is used to obtain the scheduler |
---|
807 | parameters field from the thread attribute object ``attr``. The value of this |
---|
808 | field is returned in ``param``. |
---|
809 | |
---|
810 | **NOTES:** |
---|
811 | |
---|
812 | As required by POSIX, RTEMS defines the feature symbol |
---|
813 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
814 | to which this routine belongs is supported. |
---|
815 | |
---|
816 | .. _pthread_attr_getaffinity_np: |
---|
817 | |
---|
818 | pthread_attr_getaffinity_np - Get Thread Affinity Attribute |
---|
819 | ----------------------------------------------------------- |
---|
820 | |
---|
821 | **CALLING SEQUENCE:** |
---|
822 | |
---|
823 | .. code-block:: c |
---|
824 | |
---|
825 | #define _GNU_SOURCE |
---|
826 | #include <pthread.h> |
---|
827 | int pthread_attr_getaffinity_np( |
---|
828 | const pthread_attr_t *attr, |
---|
829 | size_t cpusetsize, |
---|
830 | cpu_set_t *cpuset |
---|
831 | ); |
---|
832 | |
---|
833 | **STATUS CODES:** |
---|
834 | |
---|
835 | .. list-table:: |
---|
836 | :class: rtems-table |
---|
837 | |
---|
838 | * - ``EFAULT`` |
---|
839 | - The attribute pointer argument is invalid. |
---|
840 | * - ``EFAULT`` |
---|
841 | - The cpuset pointer argument is invalid. |
---|
842 | * - ``EINVAL`` |
---|
843 | - The ``cpusetsize`` does not match the value of ``affinitysetsize`` field |
---|
844 | in the thread attribute object. |
---|
845 | |
---|
846 | **DESCRIPTION:** |
---|
847 | |
---|
848 | The ``pthread_attr_getaffinity_np`` routine is used to obtain the |
---|
849 | ``affinityset`` field from the thread attribute object ``attr``. The value of |
---|
850 | this field is returned in ``cpuset``. |
---|
851 | |
---|
852 | **NOTES:** |
---|
853 | |
---|
854 | NONE |
---|
855 | |
---|
856 | .. _pthread_attr_setaffinity_np: |
---|
857 | |
---|
858 | pthread_attr_setaffinity_np - Set Thread Affinity Attribute |
---|
859 | ----------------------------------------------------------- |
---|
860 | |
---|
861 | **CALLING SEQUENCE:** |
---|
862 | |
---|
863 | .. code-block:: c |
---|
864 | |
---|
865 | #define _GNU_SOURCE |
---|
866 | #include <pthread.h> |
---|
867 | int pthread_attr_setaffinity_np( |
---|
868 | pthread_attr_t *attr, |
---|
869 | size_t cpusetsize, |
---|
870 | const cpu_set_t *cpuset |
---|
871 | ); |
---|
872 | |
---|
873 | **STATUS CODES:** |
---|
874 | |
---|
875 | .. list-table:: |
---|
876 | :class: rtems-table |
---|
877 | |
---|
878 | * - ``EFAULT`` |
---|
879 | - The attribute pointer argument is invalid. |
---|
880 | * - ``EFAULT`` |
---|
881 | - The cpuset pointer argument is invalid. |
---|
882 | * - ``EINVAL`` |
---|
883 | - The ``cpusetsize`` does not match the value of ``affinitysetsize`` field |
---|
884 | in the thread attribute object. |
---|
885 | * - ``EINVAL`` |
---|
886 | - The ``cpuset`` did not select a valid cpu. |
---|
887 | * - ``EINVAL`` |
---|
888 | - The ``cpuset`` selected a cpu that was invalid. |
---|
889 | |
---|
890 | **DESCRIPTION:** |
---|
891 | |
---|
892 | The ``pthread_attr_setaffinity_np`` routine is used to set the ``affinityset`` |
---|
893 | field in the thread attribute object ``attr``. The value of this field is |
---|
894 | returned in ``cpuset``. |
---|
895 | |
---|
896 | **NOTES:** |
---|
897 | |
---|
898 | NONE |
---|
899 | |
---|
900 | .. _pthread_create: |
---|
901 | |
---|
902 | pthread_create - Create a Thread |
---|
903 | -------------------------------- |
---|
904 | .. index:: pthread_create |
---|
905 | .. index:: create a thread |
---|
906 | |
---|
907 | **CALLING SEQUENCE:** |
---|
908 | |
---|
909 | .. code-block:: c |
---|
910 | |
---|
911 | #include <pthread.h> |
---|
912 | int pthread_create( |
---|
913 | pthread_t *thread, |
---|
914 | const pthread_attr_t *attr, |
---|
915 | void (*start_routine)( void *), |
---|
916 | void *arg |
---|
917 | ); |
---|
918 | |
---|
919 | **STATUS CODES:** |
---|
920 | |
---|
921 | .. list-table:: |
---|
922 | :class: rtems-table |
---|
923 | |
---|
924 | * - ``EINVAL`` |
---|
925 | - The attribute set is not initialized. |
---|
926 | * - ``EINVAL`` |
---|
927 | - The user specified a stack address and the size of the area was not large |
---|
928 | enough to meet this processor's minimum stack requirements. |
---|
929 | * - ``EINVAL`` |
---|
930 | - The specified scheduler inheritance policy was invalid. |
---|
931 | * - ``ENOTSUP`` |
---|
932 | - The specified contention scope was ``PTHREAD_SCOPE_PROCESS``. |
---|
933 | * - ``EINVAL`` |
---|
934 | - The specified thread priority was invalid. |
---|
935 | * - ``EINVAL`` |
---|
936 | - The specified scheduling policy was invalid. |
---|
937 | * - ``EINVAL`` |
---|
938 | - The scheduling policy was ``SCHED_SPORADIC`` and the specified |
---|
939 | replenishment period is less than the initial budget. |
---|
940 | * - ``EINVAL`` |
---|
941 | - The scheduling policy was ``SCHED_SPORADIC`` and the specified low |
---|
942 | priority is invalid. |
---|
943 | * - ``EAGAIN`` |
---|
944 | - The system lacked the necessary resources to create another thread, or the |
---|
945 | self imposed limit on the total number of threads in a process |
---|
946 | ``PTHREAD_THREAD_MAX`` would be exceeded. |
---|
947 | * - ``EINVAL`` |
---|
948 | - Invalid argument passed. |
---|
949 | |
---|
950 | **DESCRIPTION:** |
---|
951 | |
---|
952 | The ``pthread_create`` routine is used to create a new thread with the |
---|
953 | attributes specified by ``attr``. If the ``attr`` argument is ``NULL``, then |
---|
954 | the default attribute set will be used. Modification of the contents of |
---|
955 | ``attr`` after this thread is created does not have an impact on this thread. |
---|
956 | |
---|
957 | The thread begins execution at the address specified by ``start_routine`` with |
---|
958 | ``arg`` as its only argument. If ``start_routine`` returns, then it is |
---|
959 | functionally equivalent to the thread executing the ``pthread_exit`` service. |
---|
960 | |
---|
961 | Upon successful completion, the ID of the created thread is returned in the |
---|
962 | ``thread`` argument. |
---|
963 | |
---|
964 | **NOTES:** |
---|
965 | |
---|
966 | There is no concept of a single main thread in RTEMS as there is in a tradition |
---|
967 | UNIX system. POSIX requires that the implicit return of the main thread results |
---|
968 | in the same effects as if there were a call to ``exit``. This does not occur in |
---|
969 | RTEMS. |
---|
970 | |
---|
971 | The signal mask of the newly created thread is inherited from its creator and |
---|
972 | the set of pending signals for this thread is empty. |
---|
973 | |
---|
974 | .. _pthread_exit: |
---|
975 | |
---|
976 | pthread_exit - Terminate the Current Thread |
---|
977 | ------------------------------------------- |
---|
978 | .. index:: pthread_exit |
---|
979 | .. index:: terminate the current thread |
---|
980 | |
---|
981 | **CALLING SEQUENCE:** |
---|
982 | |
---|
983 | .. code-block:: c |
---|
984 | |
---|
985 | #include <pthread.h> |
---|
986 | void pthread_exit( |
---|
987 | void *status |
---|
988 | ); |
---|
989 | |
---|
990 | **STATUS CODES:** |
---|
991 | |
---|
992 | *NONE* |
---|
993 | |
---|
994 | **DESCRIPTION:** |
---|
995 | |
---|
996 | The ``pthread_exit`` routine is used to terminate the calling thread. The |
---|
997 | ``status`` is made available to any successful join with the terminating |
---|
998 | thread. |
---|
999 | |
---|
1000 | When a thread returns from its start routine, it results in an implicit call to |
---|
1001 | the ``pthread_exit`` routine with the return value of the function serving as |
---|
1002 | the argument to ``pthread_exit``. |
---|
1003 | |
---|
1004 | **NOTES:** |
---|
1005 | |
---|
1006 | Any cancellation cleanup handlers that hace been pushed and not yet popped |
---|
1007 | shall be popped in reverse of the order that they were pushed. After all |
---|
1008 | cancellation cleanup handlers have been executed, if the thread has any |
---|
1009 | thread-specific data, destructors for that data will be invoked. |
---|
1010 | |
---|
1011 | Thread termination does not release or free any application visible resources |
---|
1012 | including byt not limited to mutexes, file descriptors, allocated memory, |
---|
1013 | etc.. Similarly, exitting a thread does not result in any process-oriented |
---|
1014 | cleanup activity. |
---|
1015 | |
---|
1016 | There is no concept of a single main thread in RTEMS as there is in a tradition |
---|
1017 | UNIX system. POSIX requires that the implicit return of the main thread results |
---|
1018 | in the same effects as if there were a call to ``exit``. This does not occur in |
---|
1019 | RTEMS. |
---|
1020 | |
---|
1021 | All access to any automatic variables allocated by the threads is lost when the |
---|
1022 | thread exits. Thus references (i.e. pointers) to local variables of a thread |
---|
1023 | should not be used in a global manner without care. As a specific example, a |
---|
1024 | pointer to a local variable should NOT be used as the return value. |
---|
1025 | |
---|
1026 | .. _pthread_detach: |
---|
1027 | |
---|
1028 | pthread_detach - Detach a Thread |
---|
1029 | -------------------------------- |
---|
1030 | .. index:: pthread_detach |
---|
1031 | .. index:: detach a thread |
---|
1032 | |
---|
1033 | **CALLING SEQUENCE:** |
---|
1034 | |
---|
1035 | .. code-block:: c |
---|
1036 | |
---|
1037 | #include <pthread.h> |
---|
1038 | int pthread_detach( |
---|
1039 | pthread_t thread |
---|
1040 | ); |
---|
1041 | |
---|
1042 | **STATUS CODES:** |
---|
1043 | |
---|
1044 | .. list-table:: |
---|
1045 | :class: rtems-table |
---|
1046 | |
---|
1047 | * - ``ESRCH`` |
---|
1048 | - The thread specified is invalid. |
---|
1049 | * - ``EINVAL`` |
---|
1050 | - The thread specified is not a joinable thread. |
---|
1051 | |
---|
1052 | **DESCRIPTION:** |
---|
1053 | |
---|
1054 | The ``pthread_detach`` routine is used to to indicate that storage for |
---|
1055 | ``thread`` can be reclaimed when the thread terminates without another thread |
---|
1056 | joinging with it. |
---|
1057 | |
---|
1058 | **NOTES:** |
---|
1059 | |
---|
1060 | If any threads have previously joined with the specified thread, then they will |
---|
1061 | remain joined with that thread. Any subsequent calls to ``pthread_join`` on the |
---|
1062 | specified thread will fail. |
---|
1063 | |
---|
1064 | .. COMMENT: pthread_getattr_np |
---|
1065 | |
---|
1066 | .. _pthread_getattr_np: |
---|
1067 | |
---|
1068 | pthread_getattr_np - Get Thread Attributes |
---|
1069 | ------------------------------------------ |
---|
1070 | .. index:: pthread_getattr_np |
---|
1071 | .. index:: get thread attributes |
---|
1072 | |
---|
1073 | **CALLING SEQUENCE:** |
---|
1074 | |
---|
1075 | .. code-block:: c |
---|
1076 | |
---|
1077 | #define _GNU_SOURCE |
---|
1078 | #include <pthread.h> |
---|
1079 | int pthread_getattr_np( |
---|
1080 | pthread_t thread, |
---|
1081 | pthread_attr_t *attr |
---|
1082 | ); |
---|
1083 | |
---|
1084 | **STATUS CODES:** |
---|
1085 | |
---|
1086 | .. list-table:: |
---|
1087 | :class: rtems-table |
---|
1088 | |
---|
1089 | * - ``ESRCH`` |
---|
1090 | - The thread specified is invalid. |
---|
1091 | * - ``EINVAL`` |
---|
1092 | - The attribute pointer argument is invalid. |
---|
1093 | |
---|
1094 | **DESCRIPTION:** |
---|
1095 | |
---|
1096 | The ``pthread_getattr_np`` routine is used to obtain the attributes associated |
---|
1097 | with ``thread``. |
---|
1098 | |
---|
1099 | **NOTES:** |
---|
1100 | |
---|
1101 | Modification of the execution modes and priority through the Classic API may |
---|
1102 | result in a combination that is not representable in the POSIX API. |
---|
1103 | |
---|
1104 | .. _pthread_join: |
---|
1105 | |
---|
1106 | pthread_join - Wait for Thread Termination |
---|
1107 | ------------------------------------------ |
---|
1108 | .. index:: pthread_join |
---|
1109 | .. index:: wait for thread termination |
---|
1110 | |
---|
1111 | **CALLING SEQUENCE:** |
---|
1112 | |
---|
1113 | .. code-block:: c |
---|
1114 | |
---|
1115 | #include <pthread.h> |
---|
1116 | int pthread_join( |
---|
1117 | pthread_t thread, |
---|
1118 | void **value_ptr |
---|
1119 | ); |
---|
1120 | |
---|
1121 | **STATUS CODES:** |
---|
1122 | |
---|
1123 | .. list-table:: |
---|
1124 | :class: rtems-table |
---|
1125 | |
---|
1126 | * - ``ESRCH`` |
---|
1127 | - The thread specified is invalid. |
---|
1128 | * - ``EINVAL`` |
---|
1129 | - The thread specified is not a joinable thread. |
---|
1130 | * - ``EDEADLK`` |
---|
1131 | - A deadlock was detected or thread is the calling thread. |
---|
1132 | |
---|
1133 | **DESCRIPTION:** |
---|
1134 | |
---|
1135 | The ``pthread_join`` routine suspends execution of the calling thread until |
---|
1136 | ``thread`` terminates. If ``thread`` has already terminated, then this routine |
---|
1137 | returns immediately. The value returned by ``thread`` (i.e. passed to |
---|
1138 | ``pthread_exit`` is returned in ``value_ptr``. |
---|
1139 | |
---|
1140 | When this routine returns, then ``thread`` has been terminated. |
---|
1141 | |
---|
1142 | **NOTES:** |
---|
1143 | |
---|
1144 | The results of multiple simultaneous joins on the same thread is undefined. |
---|
1145 | |
---|
1146 | If any threads have previously joined with the specified thread, then they will |
---|
1147 | remain joined with that thread. Any subsequent calls to ``pthread_join`` on the |
---|
1148 | specified thread will fail. |
---|
1149 | |
---|
1150 | If value_ptr is NULL, then no value is returned. |
---|
1151 | |
---|
1152 | .. _pthread_self: |
---|
1153 | |
---|
1154 | pthread_self - Get Thread ID |
---|
1155 | ---------------------------- |
---|
1156 | .. index:: pthread_self |
---|
1157 | .. index:: get thread id |
---|
1158 | |
---|
1159 | **CALLING SEQUENCE:** |
---|
1160 | |
---|
1161 | .. code-block:: c |
---|
1162 | |
---|
1163 | #include <pthread.h> |
---|
1164 | pthread_t pthread_self( void ); |
---|
1165 | |
---|
1166 | **STATUS CODES:** |
---|
1167 | |
---|
1168 | The value returned is the ID of the calling thread. |
---|
1169 | |
---|
1170 | **DESCRIPTION:** |
---|
1171 | |
---|
1172 | This routine returns the ID of the calling thread. |
---|
1173 | |
---|
1174 | **NOTES:** |
---|
1175 | |
---|
1176 | NONE |
---|
1177 | |
---|
1178 | .. _pthread_equal: |
---|
1179 | |
---|
1180 | pthread_equal - Compare Thread IDs |
---|
1181 | ---------------------------------- |
---|
1182 | .. index:: pthread_equal |
---|
1183 | .. index:: compare thread ids |
---|
1184 | |
---|
1185 | **CALLING SEQUENCE:** |
---|
1186 | |
---|
1187 | .. code-block:: c |
---|
1188 | |
---|
1189 | #include <pthread.h> |
---|
1190 | int pthread_equal( |
---|
1191 | pthread_t t1, |
---|
1192 | pthread_t t2 |
---|
1193 | ); |
---|
1194 | |
---|
1195 | **STATUS CODES:** |
---|
1196 | |
---|
1197 | .. list-table:: |
---|
1198 | :class: rtems-table |
---|
1199 | |
---|
1200 | * - ``zero`` |
---|
1201 | - The thread ids are not equal. |
---|
1202 | * - ``non-zero`` |
---|
1203 | - The thread ids are equal. |
---|
1204 | |
---|
1205 | **DESCRIPTION:** |
---|
1206 | |
---|
1207 | The ``pthread_equal`` routine is used to compare two thread IDs and determine |
---|
1208 | if they are equal. |
---|
1209 | |
---|
1210 | **NOTES:** |
---|
1211 | |
---|
1212 | The behavior is undefined if the thread IDs are not valid. |
---|
1213 | |
---|
1214 | .. _pthread_once: |
---|
1215 | |
---|
1216 | pthread_once - Dynamic Package Initialization |
---|
1217 | --------------------------------------------- |
---|
1218 | .. index:: pthread_once |
---|
1219 | .. index:: dynamic package initialization |
---|
1220 | |
---|
1221 | **CALLING SEQUENCE:** |
---|
1222 | |
---|
1223 | .. code-block:: c |
---|
1224 | |
---|
1225 | #include <pthread.h> |
---|
1226 | pthread_once_t once_control = PTHREAD_ONCE_INIT; |
---|
1227 | int pthread_once( |
---|
1228 | pthread_once_t *once_control, |
---|
1229 | void (*init_routine)(void) |
---|
1230 | ); |
---|
1231 | |
---|
1232 | **STATUS CODES:** |
---|
1233 | |
---|
1234 | NONE |
---|
1235 | |
---|
1236 | **DESCRIPTION:** |
---|
1237 | |
---|
1238 | The ``pthread_once`` routine is used to provide controlled initialization of |
---|
1239 | variables. The first call to ``pthread_once`` by any thread with the same |
---|
1240 | ``once_control`` will result in the ``init_routine`` being invoked with no |
---|
1241 | arguments. Subsequent calls to ``pthread_once`` with the same ``once_control`` |
---|
1242 | will have no effect. |
---|
1243 | |
---|
1244 | The ``init_routine`` is guaranteed to have run to completion when this routine |
---|
1245 | returns to the caller. |
---|
1246 | |
---|
1247 | **NOTES:** |
---|
1248 | |
---|
1249 | The behavior of ``pthread_once`` is undefined if ``once_control`` is automatic |
---|
1250 | storage (i.e. on a task stack) or is not initialized using |
---|
1251 | ``PTHREAD_ONCE_INIT``. |
---|
1252 | |
---|
1253 | .. _pthread_setschedparam: |
---|
1254 | |
---|
1255 | pthread_setschedparam - Set Thread Scheduling Parameters |
---|
1256 | -------------------------------------------------------- |
---|
1257 | .. index:: pthread_setschedparam |
---|
1258 | .. index:: set thread scheduling parameters |
---|
1259 | |
---|
1260 | **CALLING SEQUENCE:** |
---|
1261 | |
---|
1262 | .. code-block:: c |
---|
1263 | |
---|
1264 | #include <pthread.h> |
---|
1265 | int pthread_setschedparam( |
---|
1266 | pthread_t thread, |
---|
1267 | int policy, |
---|
1268 | struct sched_param *param |
---|
1269 | ); |
---|
1270 | |
---|
1271 | **STATUS CODES:** |
---|
1272 | |
---|
1273 | .. list-table:: |
---|
1274 | :class: rtems-table |
---|
1275 | |
---|
1276 | * - ``EINVAL`` |
---|
1277 | - The scheduling parameters indicated by the parameter param is invalid. |
---|
1278 | * - ``EINVAL`` |
---|
1279 | - The value specified by policy is invalid. |
---|
1280 | * - ``EINVAL`` |
---|
1281 | - The scheduling policy was ``SCHED_SPORADIC`` and the specified |
---|
1282 | replenishment period is less than the initial budget. |
---|
1283 | * - ``EINVAL`` |
---|
1284 | - The scheduling policy was ``SCHED_SPORADIC`` and the specified low |
---|
1285 | priority is invalid. |
---|
1286 | * - ``ESRCH`` |
---|
1287 | - The thread indicated was invalid. |
---|
1288 | |
---|
1289 | **DESCRIPTION:** |
---|
1290 | |
---|
1291 | The ``pthread_setschedparam`` routine is used to set the scheduler parameters |
---|
1292 | currently associated with the thread specified by ``thread`` to the policy |
---|
1293 | specified by ``policy``. The contents of ``param`` are interpreted based upon |
---|
1294 | the ``policy`` argument. |
---|
1295 | |
---|
1296 | **NOTES:** |
---|
1297 | |
---|
1298 | As required by POSIX, RTEMS defines the feature symbol |
---|
1299 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
1300 | to which this routine belongs is supported. |
---|
1301 | |
---|
1302 | .. _pthread_getschedparam: |
---|
1303 | |
---|
1304 | pthread_getschedparam - Get Thread Scheduling Parameters |
---|
1305 | -------------------------------------------------------- |
---|
1306 | .. index:: pthread_getschedparam |
---|
1307 | .. index:: get thread scheduling parameters |
---|
1308 | |
---|
1309 | **CALLING SEQUENCE:** |
---|
1310 | |
---|
1311 | .. code-block:: c |
---|
1312 | |
---|
1313 | #include <pthread.h> |
---|
1314 | int pthread_getschedparam( |
---|
1315 | pthread_t thread, |
---|
1316 | int *policy, |
---|
1317 | struct sched_param *param |
---|
1318 | ); |
---|
1319 | |
---|
1320 | **STATUS CODES:** |
---|
1321 | |
---|
1322 | .. list-table:: |
---|
1323 | :class: rtems-table |
---|
1324 | |
---|
1325 | * - ``EINVAL`` |
---|
1326 | - The policy pointer argument is invalid. |
---|
1327 | * - ``EINVAL`` |
---|
1328 | - The scheduling parameters pointer argument is invalid. |
---|
1329 | * - ``ESRCH`` |
---|
1330 | - The thread indicated by the parameter thread is invalid. |
---|
1331 | |
---|
1332 | **DESCRIPTION:** |
---|
1333 | |
---|
1334 | The ``pthread_getschedparam`` routine is used to obtain the scheduler policy |
---|
1335 | and parameters associated with ``thread``. The current policy and associated |
---|
1336 | parameters values returned in``policy`` and ``param``, respectively. |
---|
1337 | |
---|
1338 | **NOTES:** |
---|
1339 | |
---|
1340 | As required by POSIX, RTEMS defines the feature symbol |
---|
1341 | ``_POSIX_THREAD_PRIORITY_SCHEDULING`` to indicate that the family of routines |
---|
1342 | to which this routine belongs is supported. |
---|
1343 | |
---|
1344 | .. COMMENT: pthread_getaffinity_np |
---|
1345 | |
---|
1346 | .. _pthread_getaffinity_np: |
---|
1347 | |
---|
1348 | pthread_getaffinity_np - Get Thread Affinity |
---|
1349 | -------------------------------------------- |
---|
1350 | |
---|
1351 | **CALLING SEQUENCE:** |
---|
1352 | |
---|
1353 | .. code-block:: c |
---|
1354 | |
---|
1355 | #define _GNU_SOURCE |
---|
1356 | #include <pthread.h> |
---|
1357 | int pthread_getaffinity_np( |
---|
1358 | const pthread_t id, |
---|
1359 | size_t cpusetsize, |
---|
1360 | cpu_set_t *cpuset |
---|
1361 | ); |
---|
1362 | |
---|
1363 | **STATUS CODES:** |
---|
1364 | |
---|
1365 | .. list-table:: |
---|
1366 | :class: rtems-table |
---|
1367 | |
---|
1368 | * - ``EFAULT`` |
---|
1369 | - The cpuset pointer argument is invalid. |
---|
1370 | * - ``EINVAL`` |
---|
1371 | - The ``cpusetsize`` does not match the value of ``affinitysetsize`` field |
---|
1372 | in the thread attribute object. |
---|
1373 | |
---|
1374 | **DESCRIPTION:** |
---|
1375 | |
---|
1376 | The ``pthread_getaffinity_np`` routine is used to obtain the ``affinity.set`` |
---|
1377 | field from the thread control object associated with the ``id``. The value of |
---|
1378 | this field is returned in ``cpuset``. |
---|
1379 | |
---|
1380 | **NOTES:** |
---|
1381 | |
---|
1382 | NONE |
---|
1383 | |
---|
1384 | .. COMMENT: pthread_setaffinity_np |
---|
1385 | |
---|
1386 | .. _pthread_setaffinity_np: |
---|
1387 | |
---|
1388 | pthread_setaffinity_np - Set Thread Affinity |
---|
1389 | -------------------------------------------- |
---|
1390 | |
---|
1391 | **CALLING SEQUENCE:** |
---|
1392 | |
---|
1393 | .. code-block:: c |
---|
1394 | |
---|
1395 | #define _GNU_SOURCE |
---|
1396 | #include <pthread.h> |
---|
1397 | int pthread_setaffinity_np( |
---|
1398 | pthread_t id, |
---|
1399 | size_t cpusetsize, |
---|
1400 | const cpu_set_t *cpuset |
---|
1401 | ); |
---|
1402 | |
---|
1403 | **STATUS CODES:** |
---|
1404 | |
---|
1405 | .. list-table:: |
---|
1406 | :class: rtems-table |
---|
1407 | |
---|
1408 | * - ``EFAULT`` |
---|
1409 | - The cpuset pointer argument is invalid. |
---|
1410 | * - ``EINVAL`` |
---|
1411 | - The ``cpusetsize`` does not match the value of ``affinitysetsize`` field |
---|
1412 | in the thread attribute object. |
---|
1413 | * - ``EINVAL`` |
---|
1414 | - The ``cpuset`` did not select a valid cpu. |
---|
1415 | * - ``EINVAL`` |
---|
1416 | - The ``cpuset`` selected a cpu that was invalid. |
---|
1417 | |
---|
1418 | **DESCRIPTION:** |
---|
1419 | |
---|
1420 | The ``pthread_setaffinity_np`` routine is used to set the ``affinityset`` field |
---|
1421 | of the thread object ``id``. The value of this field is returned in ``cpuset`` |
---|
1422 | |
---|
1423 | **NOTES:** |
---|
1424 | |
---|
1425 | NONE |
---|