write the functions reference page

[carlos-granados]

Adds reference/functions, listing the PHP functions the debugger defines in alphabetical order with parameters, return value, behaviour and an example for each. Placed after Settings in the Reference section.

Five functions, established against upstream/main at 0.3.3. The extension registers 45, but 35 are compatibility stubs in src/lib/compat_stubs.c that raise E_DEPRECATED and return a safe default. Only break, connect_to_client, info, is_debugger_active and notify do real work, and all five now exist under both prefixes — the php_debugger_* aliases have landed since the guide pages were written.

Behaviour was checked by running 0.3.3 rather than read off the stub file:

• php_debugger_info() prints the report and returns null; 'mode' returns ['debug']; 'extension-flags' returns ['control-socket']
• php_debugger_break() returns false and raises a notice with no session, unless on-demand debugging is enabled
• php_debugger_notify() returns false silently when nothing is connected
• php_debugger_is_debugger_active() is the only one with no side effects and no notices

The page closes with the xdebug_ prefix, then an info box noting that the functions from removed features still exist but do nothing and raise a deprecation.

[github-actions]

PR Preview Action v1.8.1
Preview removed because the pull request was closed.
2026-09-10 17:00 UTC