Had a sysinternals tool (filemon) for that, but now I can find something similar for the mac.
I'm a developer and I basically want to debug "file not found" or "wrong permissions" errors.
For viewing what files are accessed in real time you can leverage
fs_usage part of the FSEvents feature in Mac OS X or even
sudo fs_usage [PID].
For more info, check out the man page
https://diigo.com/0xcp0 for highlights from Brendan's blog » Top 10 DTrace scripts for Mac OS X (2011-10-10).
For more modern operating systems that are incompatible with fseventer, there's Apple Xcode Instruments –
– powerful, but (compared to fseventer) in some cases, Instruments may be too heavyweight.
You can use the dtrace opensnoop script to identify failed opens (file not found and permission errors)