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doc/FAQ.md

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+# Frequently Asked Questions
+
+---
+
+## Installation & loading
+
+**Q: profile refuses to load and prints "This profile requires Bash 4.3 or higher."**
+
+Your system's default shell is an older Bash (common on macOS, which ships
+Bash 3.x for licensing reasons). Install a newer Bash:
+```bash
+# macOS
+brew install bash
+# then add /opt/homebrew/bin/bash to /etc/shells and chsh
+```
+Or point your terminal emulator at the newer binary explicitly.
+
+---
+
+**Q: I sourced `profile.sh` but functions are not available in sub-shells or scripts.**
+
+All public functions are exported with `export -f`. They are available in
+child Bash processes, but **not** in POSIX `sh` sub-shells. Make sure your
+scripts start with `#!/usr/bin/env bash`.
+
+---
+
+**Q: I set `PROFILE_PATH` but profile still can't find its modules.**
+
+`PROFILE_PATH` must be exported *before* you source `profile.sh`:
+```bash
+export PROFILE_PATH=/opt/profile
+source /opt/profile/profile.sh
+```
+If set after sourcing, `MYPATH` is already locked in and the variable has
+no effect.
+
+---
+
+**Q: Can I load profile system-wide via `/etc/profile`?**
+
+It is not recommended. User `.bashrc` files frequently set variables that
+conflict with the aliases and locale functions defined here, leading to
+surprising behaviour. Per-user sourcing from `~/.bashrc` is the supported
+method.
+
+---
+
+## Configuration
+
+**Q: I edited `profile.conf` but my changes have no effect.**
+
+`profile.conf` is parsed once per shell session at load time. Open a new
+terminal (or `exec bash`) to pick up the changes. There is no live-reload.
+
+---
+
+**Q: How do I find out which configuration keys a module supports?**
+
+Every supported key is documented with a comment in `profile.conf`.
+See also `README.md §4.2` for a consolidated table.
+
+---
+
+**Q: A key I set in `profile.conf` is being ignored.**
+
+Check that:
+1. The key is inside the correct `[section]` header.
+2. There is no leading space before the section name (`[section]` not
+   `[ section ]`).
+3. The key is not commented out (no leading `#`).
+4. The value contains no backticks or `$(…)` — these are stripped by the
+   parser as a security measure.
+
+---
+
+## Prompt & theming
+
+**Q: How do I change the prompt theme?**
+
+Add to `profile.conf`:
+```ini
+[prompt]
+PROMPT_THEME = dark
+```
+Built-in names: `default`, `dark`, `light`, `solarized`, `solarized-light`,
+`monokai`, `monochrome`, `abyss`, `plasma`, `adwaita`.
+
+---
+
+**Q: The solarized or solarized-light theme shows wrong colours.**
+
+Those themes use 24-bit / true-colour ANSI sequences (`\e[38;2;R;G;Bm`).
+Test your terminal:
+```bash
+printf '\e[38;2;38;139;210mTrue colour test\e[0m\n'
+```
+If you see a solid blue word your terminal supports true colour.  
+If you see garbage or plain text, switch to a 16-colour theme
+(`dark`, `default`, etc.) or upgrade your terminal emulator.
+
+---
+
+**Q: I created a custom theme but `load_theme` emits "key not allowed" warnings.**
+
+Theme files are parsed, not executed. Only `PROMPT_COLOR_*` keys and the
+standard colour variable names from `disp.sh` (`Black`, `Blue`, `On_IBlack`,
+…) are accepted. Any other key — including custom variables — is rejected.
+See `README.md §4.4` for the full list of accepted keys and value forms.
+
+---
+
+**Q: Can a theme file contain shell logic or `$(…)` command substitutions?**
+
+No, and intentionally so. Theme files are parsed line-by-line; shell
+constructs are never evaluated. This is a security boundary — a malicious
+theme file cannot execute code. Values must be a colour variable reference
+(`$Blue`) or a raw ANSI escape literal (`\e[0;34m`).
+
+---
+
+## Functions
+
+**Q: `meteo` prints "No city specified" even though I set a default.**
+
+The key is `METEO_DEFAULT_CITY` (not `DEFAULT_CITY`), and it must be in the
+`[info]` section:
+```ini
+[info]
+METEO_DEFAULT_CITY = Paris
+```
+
+---
+
+**Q: `dwl` fails with "no download tool found".**
+
+`dwl` requires one of `curl`, `wget`, or `fetch` to be installed.
+Install curl:
+```bash
+# Debian / Ubuntu
+apt-get install curl
+
+# Fedora / RHEL
+dnf install curl
+```
+Or set `DWL_PREFERRED_TOOL` in `[net]` to whichever tool you have.
+
+---
+
+**Q: `pkgs` does not find packages I know are installed.**
+
+`pkgs` delegates to `dpkg -l` (Debian/Ubuntu) or `rpm -qa` (RHEL/Fedora).
+If your distribution uses a different package manager (pacman, apk, brew …)
+it is not yet supported. See `doc/todo.md` for the tracking issue.
+
+---
+
+**Q: `profile_upgrade` says "no update available" but I know there is one.**
+
+`check_updates` compares the content of the remote `version` file against
+`$PROFVERSION`. If `UPDT_DEFAULT_BRANCH` in `[updates]` points to a different
+branch than your installation, the version files may not match. Check:
+```bash
+cat "$MYPATH/version"
+```
+and make sure `UPDT_DEFAULT_BRANCH` matches the branch you track.
+
+---
+
+## Compatibility
+
+**Q: Some functions misbehave on macOS / Cygwin.**
+
+Both environments ship non-GNU userland utilities with different flags and
+behaviour. profile is primarily developed and tested on Linux (Debian and
+RHEL families). macOS and Cygwin bugs are low priority; patches that add
+compatibility without breaking Linux support are welcome.
+
+---
+
+**Q: Can I use profile with ZSH?**
+
+Not officially. Blockers include `local -A` (ZSH requires `typeset -A`) and
+`local -n` namerefs. A compatibility layer is listed in `doc/todo.md` but
+has not been implemented yet.
+
+---
+
+## Miscellaneous
+
+**Q: How do I completely disable profile for one session?**
+
+```bash
+PROFILE_DISABLED=1 bash --norc
+```
+Or simply open a shell without sourcing `~/.bashrc` (`bash --norc`).
+
+---
+
+**Q: How do I report a bug?**
+
+Open an issue on the
+[Gitea tracker](https://git.geoffray-levasseur.org/fatalerrors/profile/issues)
+or send a mail to `fatalerrors <at> geoffray-levasseur <dot> org` with:
+- The exact command that triggered the bug
+- Your OS and Bash version (`bash --version`)
+- The module involved
+- Any relevant error output