Why did IO::Select brings GLOB(0x880fe78) up as ready for reading at all, when it was opened as the write (input) filehandle?

select actually signals when a file handle needs to be serviced. In addition to "ready to read" for can_read, that includes EOF and error conditions.

In this case, the OS is ready to communicate to you that you can't read from a write-only handle.

In general, you want two select objects, one for readers and one for writers. If you want to wait for either, you'd use select instead of can_*. 

my ($r, $w) = IO::Select::select($readers_sel, $writers_sel, undef);

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I don't understand why the program terminates after writing the answer to the first question.

You only call can_read once. You appear to be missing a loop.

In reply to Re: Weirdness with IO::Select and IPC::Open3 by ikegami
in thread Weirdness with IO::Select and IPC::Open3 by rastoboy

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