c - How to simulate memory allocation errors

Question

My C application uses 3rd libraries, which do their own memory management. In order to be robust, my application has code to deal with failures of library functions due to lack of free memory.

I would like to test this code, and for this, I need to simulate failures due to lack of memory.

What tool/s are recommended for this? My environment is Linux/gcc.

Answer 1

You can use ulimit to limit the amount of resources a user can use, including memory. So you create a test user, limit their memory use to something just enough to launch your program, and watch it die :)

Example:

ulimit -m 64

Sets a memory limit of 64kb.