From: DervishD <raul@pleyades.net>
To: Jakob Oestergaard <jakob@unthought.net>,
jw schultz <jw@pegasys.ws>,
Linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: Changing argv[0] under Linux.
Date: Wed, 15 Jan 2003 18:10:09 +0100 [thread overview]
Message-ID: <20030115171009.GF86@DervishD> (raw)
In-Reply-To: <20030115164731.GB8621@unthought.net>
Hi Jakob :)
> > If execv doesn't do any magic with the supplied argv array, then
> > this should work.
> Yep, that's what I though. Can anyone shoot this down? ;)
Not me ;)) The only problem would arise if the argv[0] passed to
exec is 511 bytes long but its strlen is low, because exec can choose
to copy the array to a new location (in fact, I think it does it...).
If you provide a filled argv[0], and soon after the exec you
change it to a proper value, there is only a brief chunk of time
where argv[0] will have long and strange contents. It doesn't matter,
because you can use spaces and anyway this is not important.
[Code snippet... snipped]
> Can anyone point out a problem in the above? I'd be happy to see it shot
> down, mainly because it's ugly - and I hate programs that mess with
> argv[0].
I like your code ;))) I don't think it's ugly, on the contrary, I
find it quite elegant ;)) And I hate programs that mess with argv[0],
too. In fact, I'm against that, but I need it... You deserve an
explanation: it's a virtual console only init clone, and has a
builtin getty and login, and a builtin syslogd+klogd, too, all in
less than 17k... Well, due to the 'builtin nature' of this program,
we don't want ps show '/sbin/init' or just 'init' for the klogd
process, for example, or in the login process. We want 'ps' to show
'login' for the login process or 'klogd' for the klog builtin
emulator. That's all.
By now I just assumed that at least I had four spare characters,
but this is not true anymore when testing, since I provided init=/i
to lilo, for example. And anybody can use that parameter and screw my
init totally, just for the sake of the proc string issue :((
Your exec solution seems to be the easiest and cleanest one, and
should work, IMHO... I'm going to test right now ;))
Thanks for your help.
Raúl
next prev parent reply other threads:[~2003-01-15 17:02 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-01-14 18:59 Changing argv[0] under Linux DervishD
2003-01-14 19:10 ` Richard B. Johnson
2003-01-14 19:14 ` DervishD
2003-01-14 19:43 ` Richard B. Johnson
2003-01-14 19:50 ` DervishD
2003-01-14 19:56 ` Richard B. Johnson
2003-01-14 20:23 ` Mark Mielke
2003-01-14 20:28 ` Richard B. Johnson
2003-01-14 21:21 ` Mark Mielke
2003-01-15 14:00 ` Richard B. Johnson
2003-01-15 16:43 ` Richard B. Johnson
2003-01-15 16:57 ` DervishD
2003-01-14 22:00 ` DervishD
2003-01-21 14:16 ` Bill Davidsen
2003-01-21 15:33 ` DervishD
2003-01-14 20:25 ` Philippe Troin
2003-01-14 20:56 ` Richard B. Johnson
2003-01-14 22:04 ` DervishD
2003-01-14 23:04 ` Bob Miller
2003-01-14 23:11 ` Bob Miller
2003-01-15 4:46 ` Mark Mielke
2003-01-15 8:25 ` jw schultz
2003-01-15 11:41 ` DervishD
2003-01-15 13:16 ` Jakob Oestergaard
2003-01-15 16:22 ` DervishD
2003-01-15 16:47 ` Jakob Oestergaard
2003-01-15 17:10 ` DervishD [this message]
2003-01-15 17:36 ` Changing argv[0] under Linux. This MUST work DervishD
2003-01-15 21:26 ` Changing argv[0] under Linux Andreas Schwab
2003-01-15 21:36 ` Jesse Pollard
2003-01-15 22:03 ` DervishD
2003-01-16 9:19 ` Dorin Lazar
2003-01-15 11:35 ` DervishD
2003-01-14 21:55 ` Miquel van Smoorenburg
2003-01-14 22:04 ` Valdis.Kletnieks
2003-01-15 11:28 ` DervishD
2003-01-27 7:47 ` Anuradha Ratnaweera
[not found] <122203493@toto.iv>
2003-01-14 22:55 ` Peter Chubb
-- strict thread matches above, loose matches on Subject: below --
2003-01-16 10:12 Jon Burgess
2003-01-16 10:32 ` DervishD
2003-01-16 11:31 Jon Burgess
2003-01-16 12:58 ` DervishD
[not found] <20030116130013.GE1358@DervishD>
[not found] ` <200301161315.h0GDFLM27487@isengard.accucard.com>
2003-01-17 10:08 ` DervishD
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20030115171009.GF86@DervishD \
--to=raul@pleyades.net \
--cc=jakob@unthought.net \
--cc=jw@pegasys.ws \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox