From: u-uy74@aetey.se
To: musl@lists.openwall.com
Subject: Re: Question about setting argv[0] when manually using dynamic linker
Date: Wed, 17 May 2017 11:01:03 +0200 [thread overview]
Message-ID: <20170517070115.GL6320@example.net> (raw)
In-Reply-To: <CACBMf30_2GBzDxnLyKzm7MUJZu7-xy-SNw5eBT=xDiC-N+PQOw@mail.gmail.com>
On Tue, May 16, 2017 at 08:38:56PM -0400, John Regan wrote:
> Hi there - I was wondering if it's possible to somehow set argv[0] when
> calling the dynamic linker to load a program.
...
> I'd like to retain whatever was actually typed on the command line (in this
> case, set argv[0] to "app"), since many apps look at argv[0] to change
> behavior, ie - gzip vs gunzip.
>
> I tried seeing if there was some switch I could pass to the linker, etc -
> as far as I can tell, there's no easy way to do this.
Set argv[0] to whatever you need when you exec*() the dynamic loader,
which is straightforward with a binary wrapper (not with a shell).
A binary wrapper also adds less overhead then going through a shell.
There is imho hardly any incentive to put such functionalty into the
loader. I say this even though we are dependent here on such tricks,
to work around programs which insist on guessing things when not asked to.
Regards,
Rune
next prev parent reply other threads:[~2017-05-17 9:01 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-05-17 0:38 John Regan
2017-05-17 9:01 ` u-uy74 [this message]
2017-05-17 11:00 ` mzpqnxow
2017-05-17 16:07 ` mzpqnxow
2017-05-17 16:16 ` John Regan
2017-05-17 16:24 ` Rich Felker
2017-05-17 19:07 ` u-uy74
2017-05-17 19:16 ` John Regan
2017-05-17 21:10 ` u-uy74
2017-05-17 21:15 ` mzpqnxow
2017-05-17 21:22 ` John Regan
2017-07-02 17:36 ` u-uy74
2017-07-04 20:58 ` Rich Felker
2017-07-05 6:01 ` u-uy74
2017-07-09 9:23 ` u-uy74
2017-07-09 12:23 ` Rich Felker
2017-07-09 14:04 ` u-uy74
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