# whatfiles
Whatfiles is a Linux utility that logs what files another program reads/writes/creates/deletes on your system. It traces any new processes and threads that are created by the targeted process as well.

## Rationale:
I've long been frustrated at the lack of a simple utility to see which files a process touches from `main()` to exit. Whether you don't trust a software vendor or are concerned about malware, it's important to be able to know what a program or installer does to your system. `lsof` only observes a moment in time and `strace` is large and somewhat complicated.

## Sample output:
```
mode:  read, file: /home/theron/.gimp-2.8/tool-options/gimp-clone-tool, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/tool-options/gimp-heal-tool, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/tool-options/gimp-perspective-clone-tool, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/tool-options/gimp-convolve-tool, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/tool-options/gimp-smudge-tool, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/tool-options/gimp-dodge-burn-tool, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/tool-options/gimp-desaturate-tool, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/plug-ins, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /usr/lib/gimp/2.0/plug-ins, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /home/theron/.gimp-2.8/pluginrc, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /usr/share/locale/en_US/LC_MESSAGES/gimp20-std-plug-ins.mo, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /usr/lib/gimp/2.0/plug-ins/script-fu, syscall: openat(), PID: 8566, process: gimp
mode:  read, file: /etc/ld.so.cache, syscall: openat(), PID: 8574, process: /usr/lib/gimp/2.0/plug-ins/script-fu
mode:  read, file: /etc/ld.so.cache, syscall: openat(), PID: 8574, process: /usr/lib/gimp/2.0/plug-ins/script-fu
mode:  read, file: /usr/lib/libgimpui-2.0.so.0, syscall: openat(), PID: 8574, process: /usr/lib/gimp/2.0/plug-ins/script-fu
mode:  read, file: /usr/lib/libgimpwidgets-2.0.so.0, syscall: openat(), PID: 8574, process: /usr/lib/gimp/2.0/plug-ins/script-fu
mode:  read, file: /usr/lib/libgimpwidgets-2.0.so.0, syscall: openat(), PID: 8574, process: /usr/lib/gimp/2.0/plug-ins/script-fu
mode:  read, file: /usr/lib/libgimp-2.0.so.0, syscall: openat(), PID: 8574, process: /usr/lib/gimp/2.0/plug-ins/script-fu
mode:  read, file: /usr/lib/libgimpcolor-2.0.so.0, syscall: openat(), PID: 8574, process: /usr/lib/gimp/2.0/plug-ins/script-fu
```

## Use:

- basic use, launches `ls` and writes output to a log file in the current directory:

    `$ whatfiles ls -lah ~/Documents`

- specify output file location with `-o`:

    `$ whatfiles -o MyLogFile cd ..`

- include debug output, print to stdout rather than log file:

    `$ whatfiles -d -s apt install zoom`

- attach to currently running process (requires root privileges):

    `$ sudo whatfiles -p 1234`
    
## Distribution
Ready-to-use binaries are on the [releases](https://github.com/spieglt/whatfiles/releases) page! Someone also kindly added it to the [Arch](https://aur.archlinux.org/packages/whatfiles-git/) repository, and [letompouce](https://github.com/letompouce) set up a [GitLab](https://gitlab.com/l3tompouce/builders/whatfiles) pipeline as well.

## Compilation (requires `gcc` and `make`):
```
$ cd whatfiles
$ make
$ sudo make install
```
Supports x86, x86_64, ARM32, and ARM64 architectures.

## Questions that could be asked at some point:

- _Isn't this just a reimplementation of `strace -fe trace=creat,open,openat,unlink,unlinkat ./program`?_

  Yes. Though it aims to be simpler and more user friendly.

- _Are there Mac and Windows versions?_

  No. Tracing syscalls on Mac requires `task_for_pid()`, which requires code signing, which I can't get to work, and anyway I have no interest in paying Apple $100/year to write free software. `dtruss` on Mac can be used to follow a single process and its children, though the `-t` flag seems to only accept a single syscall to filter on. `fs_usage` does something similar though I'm not sure if it follows child processes/threads. Process Monitor for Windows is pretty great.

## Known issues:

- Tabs crash when `whatfiles` is used to launch Firefox. (Attaching with `-p [PID]` once it's running works fine, as does using `whatfiles` to launch a second Firefox window if one's already open.)

## Planned features:

- None currently, open to requests and PRs.

Thank you for your interest, and please also check out [Cloaker](https://github.com/spieglt/cloaker), [Nestur](https://github.com/spieglt/nestur), and [Flying Carpet](https://github.com/spieglt/flyingcarpet)!