HP-UX Reference (11i v3 07/02) - 7 Device (Special) Files, 9 General Information, Index (vol 10)

p
glossary(9) glossary(9)
The last three characters are the dot, underscore and hyphen characters, respectively. The hyphen should
not be used as the first character of a portable file name.
position-independent code (PIC)
Object code that can run unmodified at any virtual address. Position-independent code can use PC-relative
addressing modes and/or linkage tables. It is most often used in shared libraries, in which case the linkage
tables are initialized by the dynamic loader. Position-independent code is generated when the
+z or +Z
compiler option is specified.
privileged groups
A privileged group is a group that has had a
setprivgrp (see getprivgrp(2)) operation performed on
it, giving it access to some system calls otherwise reserved for the superuser. See appropriate
privileges.
process
An invocation of a program, or the execution of an image (see image). Although all commands and utilities
are executed within processes, not all commands or utilities have a one-to-one correspondence with
processes. Some commands (such as cd) execute within a process, but do not create any new processes.
Others (such as in the case of
ls | wc -l) create multiple processes. Several processes can be running
the same program, but each can be different data and be in different stages of execution. A process can also
be thought of as an address space and single thread of control that executes within that address space
and its required system resources. A process is created by another process issuing the fork(2) function.
The process that issues fork(2) is known as the parent process and the new process created by the fork(2)
as the child process.
process 1
See
init.
process group
Each process in the system is a member of a process group. This grouping permits the signaling of
related processes. A newly created process joins the process group of its creator.
process group ID
Each process group in the system is uniquely identified during its lifetime by a process group ID, a posi-
tive integer less than or equal to
PIC_MAX.Aprocess group ID cannot be reused by the system until
the process group lifetime ends.
process group leader
A process group leader is a process whose process ID is the same as its process group ID.
process group lifetime
A period of time that begins when a process group is created and ends when the last remaining process in
the group leaves the group, either due to process termination or by calling the setsid(2) or setpgid(2) func-
tions.
process ID
Each active process in the system is uniquely identified during its lifetime by a positive integer less than or
equal to
PID_MAX called a process ID. A process ID cannot be reused by the system until after the pro-
cess lifetime ends. In addition, if there exists a process group whose process group ID is equal to that pro-
cess ID, the process ID cannot be reused by the system until the process group lifetime ends.
process lifetime
After a process is created with a fork(2) function, it is considered active. Its thread of control and address
space exist until it terminates. It then enters an inactive state where certain resources may be returned
to the system, although some resources, such as the process ID are still in use. When another process
executes a wait(), wait3(),orwaitpid() function (see wait(2)) for an inactive process, the remain-
ing resources are returned to the system. The last resource to be returned to the system is the process ID.
At this time, the lifetime of the process ends.
program
A sequence of instructions to the computer in the form of binary code (resulting from the compilation and
assembly of program source).
262 Hewlett-Packard Company − 17 − HP-UX 11i Version 3: February 2007