Parallels C API Reference Guide
Sets the guest OS sharing auto-mount option.
If guest sharing is enabled (see PrlVmCfg_SetGuestSharingEnabled) and auto-mount is turned on, the guest OS disk drives will appear as icons on the host desktop. If sharing is enabled but auto-mount is not, you will not see the drives in the host OS but Smart Select feature will still work.
Parallels Tools must be installed to use this feature. To obtain the Parallels Tools status, use the PrlVm_GetToolsState function.