A named character vector containing at least the element
cairothe version of cairographics in use, or ""
if
cairographics is not available.
It may also contain the versions of third-party software used
by the
standard
X11-based
(not cairo-based) bitmap devices:
libpngthe version of libpng
in use, or ""
if
not available.
jpegthe version of the JPEG headers used for compilation,
or ""
if JPEG support was not compiled in.
libtiffthe version of libtiff
in use, or ""
if
not available.
Unless otherwise stated the reported version is that of the (possibly
dynamically-linked) library in use at runtime. Note that libjpeg-turbo used on some Linux distributions
reports its version as "6.2", the IJG version from which it forked.