Allow native launcher in an arbitrary subdirectory

[blueskyhigh]

Currently the native launcher must always be placed in the root of the application base directory. You can put it for example in a bin sub directory, but then app-dir also points to the sub directory and all path configuration must be relative to this directory.

It should be possible to put the native launcher in an arbitrary directory and leave only the jaunch directory in the base directory.

[ctrueden]

As a starting point to discussion, here is Claude Sonnet 4.5's initial analysis:

Current Architecture

How it works now:

1. The native launcher's location determines app-dir (the launcher's directory becomes app-dir)
2. The jaunch directory is searched in predefined locations relative to the launcher's location
3. All configuration paths are based on app-dir

Example current layout:

MyApp/                      <- app-dir points here
├── myapp                   <- launcher must be here
├── jaunch/                 <- configurator and configs
│   ├── jaunch-linux-x64
│   └── common.toml
├── lib/
└── java/

The Requested Change

Desired layout:

MyApp/                      <- app-dir should point here
├── bin/
│   └── myapp               <- launcher can be here
├── jaunch/                 <- still in root
│   ├── jaunch-linux-x64
│   └── common.toml
├── lib/
└── java/

My Thoughts

✅ This is a reasonable request

Benefits:

1. Standard Unix conventions - Many applications put executables in bin/, libraries in lib/, etc.
2. Cleaner organization - Separates executable from configuration/data
3. Multi-executable apps - If you have multiple launchers, they can all be in bin/ while sharing one jaunch config
4. Integration flexibility - Easier to integrate Jaunch-based apps into larger distributions

⚠️ Implementation Challenges

1. Breaking the launcher-location → app-dir assumption

   Currently, the configurator determines app-dir from the launcher's path. To support the requested feature, you'd need a way to specify that app-dir is somewhere else (e.g., .. or an absolute path).

   Possible approaches:

   • Environment variable: JAUNCH_APP_DIR=/path/to/app
   • Search upward for marker: Look for jaunch/ directory by walking up the directory tree
   • Configurator argument: Pass app-dir explicitly from launcher to configurator
   • Symlink support: Already partially works - you can symlink the launcher from bin/ to root

2. Jaunch directory discovery

   The C launcher currently searches for jaunch/ relative to the launcher. This would need to:

   • Search relative to app-dir instead of launcher location
   • But the launcher doesn't know app-dir until it finds and runs the configurator!

   This is a chicken-and-egg problem.

   Solutions:

   • Search upward: Walk up directory tree looking for jaunch/ directory
   • Fixed relationship: Assume jaunch is always at ../jaunch relative to launcher in bin/
   • Environment variable: JAUNCH_DIR=/path/to/app/jaunch

3. Backward compatibility

   Any solution needs to maintain backward compatibility with existing deployments where the launcher is in the root.

💡 Recommended Approach

I'd suggest a two-phase search strategy:

1. Phase 1 (preserves current behavior): Search for jaunch directory relative to launcher location (current behavior)
2. Phase 2 (new behavior): If not found, walk up directory tree looking for jaunch directory (max 3-5 levels)

Algorithm:

1. Try current locations relative to launcher dir (jaunch/, .jaunch/, etc.)
2. If not found, try parent directory: ../jaunch/, ../.jaunch/, etc.
3. If not found, try grandparent: ../../jaunch/, etc.
4. First match wins

Then update discernAppDirectory():

• Instead of always using exe directory, use the directory containing jaunch/
• This would be passed from the C launcher as a new argument

🎯 What I'd Recommend

Option A (Simple): Support the specific bin/ case

• Hardcode logic: if launcher is in bin/, app-dir is ..
• Easy to implement, covers common use case
• Not fully flexible but solves 80% of the problem

Option B (Flexible): Upward search with maximum depth

• Walk up directory tree looking for jaunch/ directory
• More flexible, handles arbitrary nesting
• Slightly more complex, but more future-proof

Option C (Explicit): Environment variable override

• Add JAUNCH_APP_DIR environment variable
• Most flexible, but requires users to set it
• Could combine with Option B as a fallback

I personally lean toward Option B (upward search) as it's self-discovering, doesn't require configuration, and handles arbitrary layouts while remaining backward compatible.

[ctrueden]

I think Claude is mostly on track here. I dislike the JAUNCH_APP_DIR variable idea, since it doesn't travel with the application portably in a file-system-only way. So setting that aside, I see three ways we can go about addressing this, from least to most general:

1. Special support for bin/
2. Walk up the directory tree looking for the jaunch configuration folder (which, to be clear, is not necessarily named jaunch—it can be named one of several things)
3. Invent a new low-level config file that sits in the same folder as the launcher executable, jaunch.ini or some such, which points to the actual app-dir as a relative path (e.g. app-dir = ..)

Like Claude, I lean toward (2), maybe with some maximum search depth.

@blueskyhigh What do you think would best meet your needs here?

[blueskyhigh]

Thanks for elaborating my request so detailed.

Option A)
I already added special support for bin/ in discernAppDirectory. and changed app-directory to ... So I could move all my binaries and jaunch-*.exe to bin/ and all my toml files to .configin the base directory.
This alternative is completely sufficient for me, and bin/ is a standard Unix Convention.

Option B)
This would be the optimal solution to traverse the directory until one of the predefined directory names is found.

Option C)
I dont' like this option either, because this requires an additional configuration in the environment.

[ctrueden]

@blueskyhigh As of 892bf2a and followup commits, the improved config discovery should be working now, enabling the native launcher to live in subfolders such as bin more easily. Please give it a try and let me know how it goes.

[blueskyhigh]

Works as a charm. Thanks a lot.