/libnss_files.so.2

libnss_files.so.2 binary

How to customize your own hosts file

As we all known, normal users can't not edit file /etc/hosts directly.

How to customize your own hosts file for your own processes without affect others?

you can use this lib to customize your own hosts file with file /code/host,

or you can edit libnss_files.so.2 replace /code/host into other path string with 10 characters.

Usage

First, edit file /code/host like following:

127.0.0.1 api.example.com
123.123.234.234 www.test.com

use LD_LIBRARY_PATH

  • save libnss_files.so.2 into a custom directory, for example, /tmp/xyz
  • then export env variable LD_LIBRARY_PATH=/tmp/xyz
  • for example:
export LD_LIBRARY_PATH=/tmp/xyz
ping api.example.com

or

LD_LIBRARY_PATH=/tmp/xyz ping api.example.com

use LD_PRELOAD

  • save libnss_files.so.2 into a custom directory, for example, /tmp/xyz
  • then export env variable LD_PRELOAD=/tmp/xyz/libnss_files.so.2
  • for example:
export LD_PRELOAD=/tmp/xyz/libnss_files.so.2
ping api.example.com

or

LD_PRELOAD=/tmp/xyz/libnss_files.so.2 ping api.example.com

Usage in Aliyun Function Compute

  • put download this lib into your project root directory;
  • new a file named host, and edit it in your project root directory;
  • update your function.
  • set ENV variable with key: LD_LIBRARY_PATH and value: /code in your function.