Can I use the c_clget[bcsilrdc] and c_clgstr functions to obtain input for a host-level task?
You can use c_clget[bcsilrdc] and c_clgstr in your host-level tasks, but there is no good reason to do this. If you use these functions to obtain the input values, you will not be taking advantage of the command line input of C programs. Moreover, you still will not have access to the IRAF parameter handling capabilities.