How to preload my .so every time an application executes?

Question

I've successfully used a hook under Linux with this article: http://hackerboss.com/overriding-system-functions-for-fun-and-profit/

Now I want to make my .so file load every time espeak loads up, no matter if it's called from another application. How do I do that?

Mat · Accepted Answer · 2012-05-07T12:05:37.703

8

You could move the espeak binary to something like espeak-real, and replace it with a small script that sets LD_PRELOAD before exec'ing espeak-real.

#! /bin/bash
export LD_PRELOAD=/your/lib.so
exec espeak-real "$@"

(stdin/out/err redirections take care of themselves.)

edited May 07 '12 at 12:05

answered May 07 '12 at 12:00

Mat

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Can you please give me example, cause I'm not good with `exec`. – blez May 07 '12 at 12:02
`exec espeak-real`. Couldn't be simpler. Unless you need to pass command line arguments? – Mat May 07 '12 at 12:02
I'll need to, yes. Even some streaming stdin. – blez May 07 '12 at 12:04
Edited with an example. – Mat May 07 '12 at 12:06
Thank you. Will it work as same as executable if I replace it? (I'm new to unix) – blez May 07 '12 at 12:11
Essentially yes. Don't forget to make your script executable. You shouldn't accept an answer before you've tested that it works (and given your comment, I don't think you have). – Mat May 07 '12 at 12:13

How to preload my .so every time an application executes?

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