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| 690 | 690 | and if it has been configured to generate interrupts (see the |
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| 691 | 691 | description of "edge"), you can poll(2) on that file and |
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| 692 | 692 | poll(2) will return whenever the interrupt was triggered. If |
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| 693 | | - you use poll(2), set the events POLLPRI and POLLERR. If you |
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| 694 | | - use select(2), set the file descriptor in exceptfds. After |
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| 695 | | - poll(2) returns, either lseek(2) to the beginning of the sysfs |
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| 696 | | - file and read the new value or close the file and re-open it |
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| 697 | | - to read the value. |
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| 693 | + you use poll(2), set the events POLLPRI. If you use select(2), |
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| 694 | + set the file descriptor in exceptfds. After poll(2) returns, |
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| 695 | + either lseek(2) to the beginning of the sysfs file and read the |
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| 696 | + new value or close the file and re-open it to read the value. |
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| 698 | 697 | |
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| 699 | 698 | "edge" ... reads as either "none", "rising", "falling", or |
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| 700 | 699 | "both". Write these strings to select the signal edge(s) |
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