C language equivalent in late 70's would have been user defined array of functions (flyweight threads); use of fork()/exec() system call. (vs. current threads a

C language equivalent in late 70's would have been user defined array of functions (flyweight threads); use of fork()/exec() system call. (vs. current threads abstraction library/api) Closest thing to direct "in-language thread concept" would be proposed C language definition addtion in which source code could specify a case statment block(s) be assigned to run on different cpu core(s) than the running program.