/usr/share/doc/ is in libsylph-dev 1.1.0-15.
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/usr/share/doc/libsylph-dev/examples/
/usr/share/doc/libsylph-dev/examples/libsylph-listprefs.c
/usr/share/doc/libsylph-dev/examples/libsylph-pop.c
/usr/share/doc/libsylph-dev/examples/libsylph-send.c
/usr/share/doc/libsylph-dev/examples/libsylph-listsummary.c
/usr/share/doc/libsylph-dev/examples/README
/usr/share/doc/libsylph-dev/examples/README.ja
/usr/share/doc/libsylph-dev/examples/libsylph-listfolder.c
/usr/share/doc/libsylph-dev/examples/libsylph-compose.c
/usr/share/doc/libsylph-dev/examples/libsylph-template.c
/usr/share/doc/libsylph-dev/examples/libsylph-createmailbox.c
/usr/share/doc/libsylph-dev/copyright
/usr/share/doc/libsylph-dev/TODO
/usr/share/doc/libsylph-dev/README.ja.gz
/usr/share/doc/libsylph-dev/README.gz
/usr/share/doc/libsylph-dev/NEWS.gz
/usr/share/doc/libsylph-dev/changelog.Debian.gz