Presumably my script above is unsafe in the general case - I imagine libc could readahead 4k and not finish on a line boundary, then the second process would call readline and start halfway through a line.

Correct.

Why do you want two processes to read the same file?

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^3: confusing fork/readline behaviour by afoken
in thread confusing fork/readline behaviour by flipper

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