OSX Library Preload

This technique is effectively equivalent to Windows: Inject Into Suspended Process but officially supported at the OS level.

Run the target process with DYLD_INSERT_LIBRARIES=path/to/your/library.so command args...

For more details see: Linux Preload.

Issue: Disabled by Default?

Error

Reportedly you may need to disable System Integrity Protection (SIP) in order to use it in some cases (I believe only for binaries signed by Apple though).

Unfortunately, I do not have an Apple machine.