Hoist Your Applications with petardfs

“The petard filesystem is designed to produce only errors–but
you can stipulate what conditions generate the errors and what
those errors should be. That makes petardfs useful for system and
unit testing–for example, making sure that an application gives a
sane error message if it fails to open a file, or if there is a
read error at byte 5000 of a file.

“Petardfs uses Filesystem in Userspace (FUSE) to allow easy
setup without requiring a kernel recompile or new kernel modules.
In normal configuration you specify a ‘base filesystem’ and give a
mountpoint–for example, saying that /home/ben/foo is the base
filesystem and mounting the filesystem at