  Radial velocity measurements, $BVR_C$ photometry, and high-resolution
spectroscopy in the wavelength region from blue to near infrared are employed
in order to clarify the evolutionary status of the carbon-enhanced metal-poor
star HD112869 with unique ratio of carbon isotopes in the atmosphere. An LTE
abundance analysis was carried out using the method of spectral synthesis and
new self consistent 1D atmospheric models. The radial velocity monitoring
confirmed semiregular variations with a peak-to-peak amplitude of about 10 km
$s^{-1}$ and a dominating period of about 115 days. The light, color and radial
velocity variations are typical of the evolved pulsating stars. The atmosphere
of HD112869 appears to be less metal-poor than reported before, [Fe/H] = -2.3
$\pm$0.2 dex. Carbon to oxygen and carbon isotope ratios are found to be
extremely high, C/O $\simeq$ 12.6 and $^{12}C/^{13}C \gtrsim$ 1500,
respectively. The s-process elements yttrium and barium are not enhanced, but
neodymium appears to be overabundant. The magnesium abundance seems to be lower
than the average found for CEMP stars, [Mg/Fe] < +0.4 dex. HD112869 could be a
single low mass halo star in the stage of asymptotic giant branch evolution
