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Re: Why is this outputting alternate blank lines?

From Joe Pfeiffer <pfeiffer@cs.nmsu.edu>
Newsgroups comp.lang.c
Subject Re: Why is this outputting alternate blank lines?
Date 2016-12-14 20:40 -0700
Organization A noiseless patient Spider
Message-ID <1bfulpuage.fsf@pfeifferfamily.net> (permalink)
References (5 earlier) <o2s8ir$uk5$1@dont-email.me> <1b1sxauo96.fsf@pfeifferfamily.net> <o2skdb$cfs$1@dont-email.me> <1btwa6t4ij.fsf@pfeifferfamily.net> <o2soqd$och$1@dont-email.me>

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Richard Heathfield <rjh@cpax.org.uk> writes:

> On 15/12/16 00:33, Joe Pfeiffer wrote:
>> Richard Heathfield <rjh@cpax.org.uk> writes:
>>
>>> I did, and practically every application I tried to use would fall
>>> over within a few minutes (or, sometimes, within a few seconds).
>>
>> That's weird.  How much swap did you have?
>
> Several tons. Truckloads.

Wow.  All I can say is that's surprising.

>> Well, they're expecting overcommit.
>
> Well, they shouldn't.

You have to have expectations.  If 99+% of the systems you're running on
have overcommit, it's not a bad assumption.  The only other real
possibility is to have some sort of developer-accessible way to check
the memory pool to decide whether you really need to crash, or if you
can continue.  If that exists, I'm not aware of it.

>> It's pretty close to true
>> (especially on a 64 bit system) with overcommit that the only time
>> malloc() will fail is if something has corrupted the memory pool; in
>> that case, you might as well crash now since you're going to very soon
>> (or worse).
>
> Or you might as well not bother testing, which is what I suspect
> happens most of the time. And that's why Linux software is so
> hopeless. Not as hopeless as Windows software, obviously --- but still
> pretty hopeless. Look! Shiny!

Well, yeah.  Most programmers expect all library and system calls (even
open()!) to succeed and don't check anything.  The question here is, for
that tiny fraction who check at all, what should they do?  I try to do
something sane if it's likely to be a user error, and crash with an
error message if it's mine.  If malloc() fails, it's almost certain
that I've got a wild pointer someplace.

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Thread

Why is this outputting alternate blank lines? DFS <nospam@dfs.com> - 2016-12-13 23:18 -0500
  Re: Why is this outputting alternate blank lines? Melzzzzz <mel@zzzzz.com> - 2016-12-14 05:30 +0100
  Re: Why is this outputting alternate blank lines? mark.bluemel@gmail.com - 2016-12-14 00:59 -0800
  Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-14 10:38 +0000
    Re: Why is this outputting alternate blank lines? DFS <nospam@dfs.com> - 2016-12-14 12:53 -0500
      Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-14 18:05 +0000
        Re: Why is this outputting alternate blank lines? Keith Thompson <kst-u@mib.org> - 2016-12-14 11:57 -0800
          Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-14 20:05 +0000
            Re: Why is this outputting alternate blank lines? "James R. Kuyper" <jameskuyper@verizon.net> - 2016-12-14 15:21 -0500
            Re: Why is this outputting alternate blank lines? Keith Thompson <kst-u@mib.org> - 2016-12-14 12:28 -0800
              Re: Why is this outputting alternate blank lines? supercat@casperkitty.com - 2016-12-14 13:09 -0800
              Re: Why is this outputting alternate blank lines? Jean-Marc Bourguet <jm@bourguet.org> - 2016-12-14 22:53 +0100
                Re: Why is this outputting alternate blank lines? <william@wilbur.25thandClement.com> - 2016-12-14 15:47 -0800
            Re: Why is this outputting alternate blank lines? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-12-14 15:41 -0700
              Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-14 23:26 +0000
                Re: Why is this outputting alternate blank lines? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-12-14 17:33 -0700
                Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-15 00:42 +0000
                Re: Why is this outputting alternate blank lines? supercat@casperkitty.com - 2016-12-14 17:05 -0800
                Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-15 08:21 +0000
                Re: Why is this outputting alternate blank lines? supercat@casperkitty.com - 2016-12-15 09:15 -0800
                Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-15 17:50 +0000
                Re: Why is this outputting alternate blank lines? supercat@casperkitty.com - 2016-12-15 12:15 -0800
                Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-15 20:37 +0000
                Re: Why is this outputting alternate blank lines? raltbos@xs4all.nl (Richard Bos) - 2016-12-15 20:08 +0000
                Re: Why is this outputting alternate blank lines? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-12-14 20:40 -0700
                Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-15 08:36 +0000
                Re: Why is this outputting alternate blank lines? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-12-15 17:43 -0700
                Re: Why is this outputting alternate blank lines? Richard Heathfield <rjh@cpax.org.uk> - 2016-12-16 01:05 +0000
                Re: Why is this outputting alternate blank lines? Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2016-12-15 18:34 -0700
                Re: Why is this outputting alternate blank lines? <william@wilbur.25thandClement.com> - 2016-12-15 10:14 -0800
                Re: Why is this outputting alternate blank lines? raltbos@xs4all.nl (Richard Bos) - 2016-12-15 20:15 +0000
            Re: Why is this outputting alternate blank lines? Tim Rentsch <txr@alumni.caltech.edu> - 2016-12-15 01:51 -0800
              Re: Why is this outputting alternate blank lines? asetofsymbols@gmail.com - 2016-12-15 06:09 -0800
                Re: Why is this outputting alternate blank lines? Tim Rentsch <txr@alumni.caltech.edu> - 2016-12-15 17:47 -0800
          Re: Why is this outputting alternate blank lines? Keith Thompson <kst-u@mib.org> - 2016-12-14 12:15 -0800
            Re: Why is this outputting alternate blank lines? <william@wilbur.25thandClement.com> - 2016-12-15 10:24 -0800
          Re: overcommit is the plague Noob <root@127.0.0.1> - 2016-12-17 01:17 +0100
      Re: Why is this outputting alternate blank lines? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-14 20:19 +0000
        Re: Why is this outputting alternate blank lines? DFS <nospam@dfs.com> - 2016-12-14 17:44 -0500
          Re: Why is this outputting alternate blank lines? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-15 00:21 +0000
            Re: Why is this outputting alternate blank lines? mark.bluemel@gmail.com - 2016-12-15 00:56 -0800
              Re: Why is this outputting alternate blank lines? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-12-15 22:08 +0000
      Re: Why is this outputting alternate blank lines? Geoff <geoff@invalid.invalid> - 2016-12-14 13:39 -0800
      Re: Why is this outputting alternate blank lines? Ike Naar <ike@iceland.freeshell.org> - 2016-12-16 07:12 +0000

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