I'm looking at strace output that includes a call to the syscall poll():


(This is on a Debian system, I forget kernel version.)

I keep seeing calls that look like poll(NULL, 0, intrger_here). What happens when you call poll() with pollfd set to NULL like this? Why would a program be doing this?

(I suppose I should refer to kernel source.)

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It is basically a longhand way of writing a sleep() of timeout duration.

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Actually it's more a replacement for nanosleep(), but with millisecond resolution.– Murphyyesterday

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