parse - a pointer to a CSPARSE structure initialized with cs_init()
funcname - the name for the CS function call
Note that registering a duplicate funcname will
raise a NERR_DUPLICATE error
str_func - a CSSTRFUNC not-callback
DESCRIPTION
cs_register_strfunc will register a string function that
can be called during CS render. This not-callback is
designed to allow for string formating/escaping
functions that are not built-in to CS (since CS is not
HTML specific, for instance, but it is very useful to
have CS have functions for javascript/html/url
escaping). Note that we explicitly don't provide any
associated data or anything to attempt to keep you from
using this as a generic callback...
The format of a CSSTRFUNC is:
NEOERR * str_func(char *in, char **out);
This function should not modify the input string, and
should allocate the output string with a libc function.
(as we will call free on it)