Message200823
> 3- From another process, like bash, continuously write to the file.
That's the problem: reducing (actually truncating in your case) a file currently mmaped *can only result in a core dump*: when you try to read from a location in memory which doesn't correspond anymore to a position in the file (since it got truncated), which value could the kernel return?
The page you're trying to read from isn't mapped anymore, so you get a segfault.
Apparently it's even documented in the main page:
"""
The effect of changing the size of the underlying file of a mapping on the pages that correspond to added or removed regions of
the file is unspecified.
""" |
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Date |
User |
Action |
Args |
2013-10-21 18:33:57 | neologix | set | recipients:
+ neologix, pitrou, vstinner, sbt, serhiy.storchaka, rbhkamal |
2013-10-21 18:33:57 | neologix | set | messageid: <1382380437.54.0.514189296802.issue19337@psf.upfronthosting.co.za> |
2013-10-21 18:33:57 | neologix | link | issue19337 messages |
2013-10-21 18:33:57 | neologix | create | |
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