What's New in fswatch v. 1.21.0:

fswatch v. 1.21.0 introduces the following features and bug fixes:

• CLI, Issues 104 and 273: Add --filter-mode=conjunctive. In this mode, include filters define the candidate set and exclude filters subtract from it: a path is accepted when it matches an include filter, or when no include filters are specified, and does not match any exclude filter.

• CLI, Issue 151: Add --prune to prevent recursive traversal from descending into matching directories where the selected monitor performs traversal in fswatch or libfswatch. This is distinct from --exclude: --exclude filters emitted events, while --prune prevents recursive descent into matching subtrees.

• Compatibility: Legacy include/exclude filter behavior remains the default. In legacy mode, include filters may still override exclude filters.

• Issue 305: Install CMake package configuration files for libfswatch so CMake consumers can use find_package(libfswatch CONFIG).

• Bug fix, Issue 247: Keep explicit root paths eligible for monitor setup even when path filters would reject the root path itself, allowing matching children to be discovered and reported.

• Issue 238: Document the BSD/macOS xargs replacement-string length caveat when processing fswatch output with xargs -I.

• Add filtering regression coverage for legacy and conjunctive filter modes, root-path eligibility, and traversal pruning.

libfswatch v. 1.21.0 introduces the following features and bug fixes:

• API, Issues 104 and 273: Add conjunctive path filter evaluation mode. In this mode, inclusion filters define the candidate set and exclusion filters subtract from it: a path is accepted when it matches an inclusion filter, or when no inclusion filters are specified, and does not match any exclusion filter.

• API, Issue 151: Add traversal prune filters so recursive monitors can skip matching directories before scanning or watching their descendants. Prune filters are separate from normal path filters: normal exclude filters reject emitted events, while prune filters prevent recursive descent where the monitor performs library-side traversal.

• API: Add C API support for filter mode selection and prune filters.

• Compatibility: Legacy filter behavior remains the default.

• Compatibility: The public C++ fsw::monitor layout changed. Existing compiled C++ clients should be rebuilt against this release. The libfswatch libtool release version is 15:0:0.

• Bug fix, Issue 247: Keep explicit root paths eligible for monitor setup even when path filters would reject the root path itself, allowing matching children to remain discoverable.

• Issue 305: Install CMake package configuration files and exported targets for libfswatch so CMake consumers can use find_package(libfswatch CONFIG).

• Add regression coverage for filter modes, root-path eligibility, traversal pruning, and the new C API pruning entry point.

Upgrade and Compatibility Notes

• Legacy include/exclude filter behavior remains the default. Use --filter-mode=conjunctive to opt into include-as-candidate-set semantics.

• --exclude and --prune serve different purposes. --exclude filters emitted events. --prune prevents recursive traversal from descending into matching directories where the selected monitor performs library-side traversal.

• Explicit command-line root paths remain eligible for monitoring even when path filters would reject the root path itself.

• libfswatch adds C API entry points for filter mode selection and prune filters.

• The public C++ fsw::monitor layout changed. C++ clients should be rebuilt against this release. The libtool release version is 15:0:0.