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by nikeee 112 days ago
So if i happen to know the numbers of other file descriptors of the process (listed in /proc), i can redirect to other files opened in the current process? 2>&1234? Or is it restricted to 0/1/2 by the shell?

Would probably be hard to guess since the process may not have opened any file once it started.
2 comments
hugmynutus 112 days ago
> Or is it restricted to 0/1/2 by the shell?

It is not. You can use any arbitrary numbers provided they're initialized properly. These values are just file descriptors.

For Example -> https://gist.github.com/valarauca/71b99af82ccbb156e0601c5df8...

I've used (see: example) to handle applications that just dump pointless noise into stdout/stderr, which is only useful when the binary crashes/fails. Provided the error is marked by a non-zero return code, this will then correctly display the stdout/stderr (provided there is <64KiB of it).

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viraptor 112 days ago
No restrictions. You can create your own beautiful monsters that way.

> Would probably be hard to guess since the process may not have opened any file once it started.

You need to not only inspect the current state, but also race the process before the assignments change.

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