红帽全球峰会8.8. CAS(1)
8.8.1. NAME
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cas - 在强计数器上执行"compare-and-swap"操作。
8.8.2. SYNOPSIS
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cas ['OPTIONS'] ['COUNTER_NAME']
8.8.3. 选项
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- --expect='nnn'
- 指定计数器的预期值。
- --value='nnn'
- 为计数器设置一个新值。
- -q, --quiet='[true|false]'
- 隐藏返回值。默认值为 false。
8.8.4. 示例
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cas --expect=10 --value=20 cnt_a
只有在当前值设为 10时，才会将 cnt_a 的值设置为 20
8.8.5. 另请参阅
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add(1), cas(1), reset(1)
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