Modify program behavior with LD_PRELOAD

Conclusions

There are no limits to your creativity when using LD_PRELOAD. Discover frequently used library functions, write a wrapper for them, and introduce minor changes. If you define and export the variable in a shell, it will apply to all processes you launch in that shell, without you needing to prepend the definition to each command.

Infos

  1. GNU C Library: https://www.gnu.org/software/libc/
  2. strace: https://github.com/strace/strace
  3. ltrace: https://gitlab.com/cespedes/ltrace
  4. Awesome LD_PRELOAD: https://github.com/gaul/awesome-ld-preload

The Author

Hans-Georg Eßer is professor for operating systems at South Westphalia University of Applied Sciences. Prior to his academic career, he worked in magazine publishing, most recently as editor-in-chief of EasyLinux.

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