From: Mike Frysinger <vapier@gentoo.org>
To: 肖鹏 <xiaopeng_phy@163.com>
Cc: libc-help@sourceware.org
Subject: Re: glibc interception problems
Date: Mon, 24 May 2021 23:10:35 -0400 [thread overview]
Message-ID: <YKxqqwDeWypwZfdJ@vapier> (raw)
In-Reply-To: <cd6040e.12c1.179a15c68cf.Coremail.xiaopeng_phy@163.com>
On 25 May 2021 10:30, 肖鹏 via Libc-help wrote:
> I'm developping a library for a distributed file system, using LD_PRELOAD to intercept file related calls to glibc.
> Programs directly using unbuffered IO (close/open/read/write) work well with my library. But programs using buffered IO (fclose/fopen/fread/fwrite) will call unbuffered functions of glibc instead of my library.
> The reason is that in glibc, buffered IO depend on internal symbols, which cannot be intercepted.
> I can see two ways to work around this:
> 1. Implement buffered IO in my library.
> 2. Modify glibc buffered IO to use public symbols, and maintain a custom version of glibc.
> Both ways have drawbacks. Do you have any suggestions about this?
what is your end goal ?
is this a research project ?
are you developing an open source project that you want to share with others ?
something else ?
if it's a short-term project (e.g. for research), (2) might be your best bet.
it's hacky, but if it gathers the info you need, it's not that bad.
if it's a long-term project you want to share with others, i'd recommend not
using LD_PRELOAD at all. maybe FUSE would be better.
-mike
next prev parent reply other threads:[~2021-05-25 3:10 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-25 2:30 肖鹏
2021-05-25 3:10 ` Mike Frysinger [this message]
[not found] ` <4f73c540.6a6.179a6344524.Coremail.xiaopeng_phy@163.com>
2021-05-26 3:47 ` Mike Frysinger
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