dl-search.c is shared with sigil-audio

This file is the origin; sigil-audio carries a byte-identical copy (src/c/dl-search.c there, with -DSIGIL_DL_SEARCH_INTERPOSE=0 and the sigil_audio_* names). Each repository records the hash below and its test/dl-search-test.sh refuses a file whose hash differs, so a change on either side reddens a test until the file is copied across and the hash re-recorded in both.

sha256 of src/c/dl-search.c:

c3495d28b963ff5defe58375153c96e4d9e86ced6b9d3e4fa1fbb234bac3881a

To change it: edit here, run this repository's test (it fails on the old hash), update the hash above, copy the file and the hash to sigil-audio's src/c/dl-search.c and src/c/DL-SEARCH-ORIGIN.md, run its test.