Make a copy instead of a link if the original file is writable.

Create a set_fd_user function.
Update create_file() to use the above functions.

to the real libc functions instead.

- pass heap to allocate from directly to helper functions, instead of
  unnecessarily copying returned data
- use public types rather than internal ones
- make sure GetBestRoute doesn't return bogus matches

Correctly identify structures containing varying arrays as conformant
varying structures.

Rename has_conformant_array to has_conformance, add a new variable
has_variance and map has_conformant_string to has_conformance and
has_variance.
A conformant varying struct should be returned if just variance is
present and even if no pointers are present.

Conformant arrays should cause a size of 0 to be returned from
type_memsize.

Fix detection of conformant arrays and output an error if the array
isn't at the end of the structure.

Write out type format string for simple structs and for pointers to
non-simple types.

Support pointer types in unmarshall_arguments.

Add functions for detecting array and string types and use these in
both writing type format strings and when marshalling and
unmarshalling parameters.

Write out type format strings for string types.

Write out type format strings for arrays, except for the missing
generic functionality of conformance and variance descriptors.

Simplify handling of types in write_typeformatstring_type by only
writing non-pointer types out when ptr_level is 0. Add stubs for
functions that will write out the type format string for strings and
arrays.

Since a var_t can now be passed in, rename to
write_typeformatstring_var. Simplifies the code.

Renamed to write_procformatstring_var now since we can pass a var_t in
again. This results in simpler code.

Uwe Bonnes).