From: Rich Felker <dalias@aerifal.cx>
To: musl@lists.openwall.com
Subject: Re: Anti-bloat side project
Date: Tue, 16 Aug 2011 09:52:32 -0400 [thread overview]
Message-ID: <20110816135232.GR132@brightrain.aerifal.cx> (raw)
In-Reply-To: <20110816131610.GG26140@barfooze.de>
On Tue, Aug 16, 2011 at 03:16:10PM +0200, Moritz Wilhelmy wrote:
> On Tue, Aug 16, 2011 at 09:06:43 -0400, Rich Felker wrote:
> > Is it possibly implemented as a shell script? The way the shell "read"
> > command works, it's required to perform byte-at-a-time reads like
> > this. Otherwise, I'm guessing someone just foolishly turned off
> > buffering on the FILE...
>
> In fact, it really is a C program, and sadly, it seems they really
> implement it that way (by greping over the code for about 30 seconds);
>
> See src/mygetline.c on hg tip[1]:
> 41 while(1) {
> 42 res = read(fd, &ch, 1);
>
> Maybe coders need to be educated about how not to write code in order to
> avoid (syscall-)bloat?
>
> [1]: http://mlmmj.org/hg/mlmmj/file/tip/src/mygetline.c
As they're using a file descriptor rather than a FILE or their own
higher-level buffering structure, the design forces them to either
require that the file descriptor be seekable (so they can seek back
after reading too much) or read one byte at a time.
I'm not sure why someone would use file descriptors rather than stdio
or something similar for processing text.. Looks lke just a bad
design. There's no immediate fix, however, as the issue is a result of
the design.
Rich
prev parent reply other threads:[~2011-08-16 13:52 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-27 17:08 Rich Felker
2011-06-27 21:16 ` Szabolcs Nagy
2011-06-27 21:19 ` Rich Felker
2011-06-27 21:38 ` Szabolcs Nagy
2011-06-27 21:37 ` Rich Felker
2011-06-27 21:43 ` Rich Felker
2011-06-29 14:19 ` Szabolcs Nagy
2011-06-29 19:27 ` Rich Felker
2011-06-29 20:03 ` Szabolcs Nagy
2011-08-16 13:03 ` Moritz Wilhelmy
2011-08-16 13:06 ` Rich Felker
2011-08-16 13:16 ` Moritz Wilhelmy
2011-08-16 13:52 ` Rich Felker [this message]
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