Is there something to replace the functions?

Question

The user thread functions in are deprecated because they use a deprecated C feature (they use a function declaration with empty parentheses f

Answer 1

No, there is no standard replacement for them.

You options are

• continue to use even though they contain obsolete C.
• switch to pthreads
• write your own co-thread library
• use an existing (and possibly not-so-portable) co-thread library such as http://swtch.com/libtask/ , though many of such libraries are implemented on top of ucontext.h