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Groups > gnu.bash.bug > #11360

Re: Integer Overflow in braces

From Greg Wooledge <wooledg@eeg.ccf.org>
Newsgroups gnu.bash.bug
Subject Re: Integer Overflow in braces
Date 2015-08-17 08:20 -0400
Message-ID <mailman.8480.1439814061.904.bug-bash@gnu.org> (permalink)
References <CABq52TYThGj9OtBn3xTti5scmA=WdnS7ULw3G6GMayPK6WR0+w@mail.gmail.com>

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On Sat, Aug 15, 2015 at 08:53:55PM -0700, Pasha K wrote:
> (gdb) r -c "for x in {1..9223372036854775805}; do echo overflow; done"

Brace expansion requires bash to generate and store ALL of those strings
in memory simultaneously.  I seriously doubt any computer on earth has
enough virtual memory to hold what you've asked for here.  (Unless I'm
miscounting, you've asked bash to generate over 900 quintillion strings
of length varying from 1 to 19 bytes in length (2 to 20 with NULs).)

If you want to count to a large number, use a C-style for loop instead
of a brace expansion.

for ((x=1; x<=9000000000; x++)); do ...; done

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Re: Integer Overflow in braces Greg Wooledge <wooledg@eeg.ccf.org> - 2015-08-17 08:20 -0400

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