A "process" is a program. In multitasking environments such as Unix or Windows - in fact, in most modern operating systems - the computer can run multiple processes at the same time. Note that not all of such processes need to have a visible window - some can be hidden from the user, until you use a special tool or command to list the processes.
A process is a piece of code running on a Unix server. The code is programmed to do a specific job.
For example struct tm and struct stat are often used by UNIX processes.
Advanced Programming in the Unix Environment was created in 1992.
Unix configuration is the process of tailoring a freshly installed version of Unix to your particular environment. Each Unix system may do that differently.
ps -ef
Some versions of Unix are oriented towards real time applications, and processes in Unix can be "promoted" to real time status if desired. Other than that, you would have to define more precisely what you mean by real time for an operating system.
In a sense, I suppose you could say it was a descendant of Unix; it is actually a clone of the Unix environment and Operating System.
You can have as many processes as will fit in the process table and remain comfortably in memory (which is a lot).
Depends on what you mean by a "gnu" file, since utilities are common across Unix platforms including HPUX. Need more information.
Solaris is a specific version of Unix; the term 'Unix' refers to a classification, and several vendors provide a Unix-like environment. So, in a sense, Unix and Solaris are the same thing.
In Unix, pipes are basically how information flows between processes. Unnamed pipes are created and destroyed within the processes life cycle. Named pipes exist until removed with an unlink() command and can be used with unrelated processes.
PS -eaf|grep defunct
If your application or environment warrants it, sure..