These routine process creation task are done irrespective of whether its for a C program or a Java or a PHP program.
Plus it is not necessary for programs written in languages other than C(or even C) to use the C standard library. Hence we cannot put all these routine tasks in a C standard library.
For e.g., in case of Linux systems, the "program loader" and "dynamic linker" are not part of the gnu c library. They are the part of separate "binutils" package.
This link though a bit dated will give you a fair amount of information on the journey of writing a program to a running process. It uses gcc/Linux but major tasks are the similar on other platforms.
EDIT /* THE DYNAMIC LINKER IS A PART OF GLIBC...THANKS TO employedrussian */