notmuch/compat This directory consists of three things: 1. Small programs used by the notmuch configure script to test for the availability of certain system features, (library functions, etc.). For example: have_getline.c 2. Compatibility implementations of those system features for systems that don't provide their own versions. For example: getline.c The compilation of these files is made conditional on the output of the test programs from [1]. 3. Macro definitions abstracting compiler differences (e.g. function attributes). For example: function-attributes.h