Can I guarantee atomic addition in Ruby?

Question

Based Is the append file atomic on UNIX? and other sources, it looks like modern Linux, I can open the file in add mode and write small fragments (< PIPE_BUF) to it from several processes, without worrying about the break.

Are these Ruby limits limited by syswrite? In particular, for this code:

f = File.new('...', 'a')
f.syswrite("short string\n")

Is it possible to expect that the record will not alternate with another process written the same way? Or is there some kind of buffering / potential splitting that I don't know about yet?

Assuming ruby> = 2.3

Answer 1

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: POSIX 'read() write() Atom?

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Answer 2

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