HP-UX Reference (11i v2 03/08) - 5 Miscellaneous Topics, 7 Device (Special) Files, 9 General Information, Index (vol 9)
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glossary(9) glossary(9)
parent process
Whenever a new process is created by a currently-existing process (via fork(2)), the
currently existing process is said to be the parent process of the newly created process.
Every process has exactly one parent process (except the
init process, see init), but
each process can create several new processes with the fork(2) system call. The parent
process ID of any process is the process ID of its creator.
parent process ID
A new process is created by a currently active process. The parent process ID of a pro-
cess is the process ID of its creator for the lifetime of the creator. After the creator’s life-
time has ended, the parent process ID is the process ID of
init.
password A string of ASCII characters used to verify the identity of a user. Passwords can be asso-
ciated with users and groups. If a user has a password, it is automatically encrypted and
entered in the second field of that user’s line in the
/etc/passwd file. A user can
create or change his or her own password by using the passwd(1) command.
path name A sequence of directory names separated by slashes, and ending with any file name. All
file names except the last in the sequence must be directories. If a path name begins
with a slash (
/), it is an absolute path name; otherwise, it is a relative path name.
A path name defines the path to be followed through the hierarchical file system in order
to find a particular file.
More precisely, a path name is a null-terminated character string constructed as follows:
<path-name>::=<file-name><path-prefix><file-name>
/
<path-prefix>::=<rtprefix>/<rtprefix>
<rtprefix>::=<dirname>
/<rtprefix><dirname>/
where <file-name> is a string of one or more characters other than the ASCII slash and
null, and <dirname> is a string of one or more characters (other than the ASCII slash
and null) that names a directory. File and directory names can consist of up to 14 char-
acters on systems supporting short file names and up to 255 characters on systems sup-
porting long file names.
A slash (
/) by itself names the root directory. Two or more slashes in succession
(////...) are treated as a single slash.
Unless specifically stated otherwise, the null or zero-length path name is treated as
though it named a nonexistent file.
path name resolution
The process that resolves a path name to a particular file in a file hierarchy.Multiple
path names can resolve to the same file, depending on whether resolution is sought in
absolute or relative terms (see below). Each file name in the path name is located in the
directory specified by its predecessor (for example, in the path name fragment
a/b,file
b
is located in directory a). Path name resolution fails if this cannot be accomplished.
If the path name begins with a slash, the predecessor of the first file name in the path
name is understood to be the root directory of the process, and the path name is
referred to as an absolute path name. If the path name does not begin with a slash,
the predecessor of the first file name of the path name is understood to be the current
working directory of the process, and the path name is referred to as a relative path
name. A path name consisting of a single slash resolves to the root directory of the pro-
cess.
path prefix A path name with an optional ending slash that refers to a directory.
permission bits
The nine least-significant bits of a file’s mode are referred to as file permission bits.
These bits determine read, write, and execute permissions for the file’s owner, the file’s
group, and all others. The bits are divided into three parts: owner, group and other.
Each part is used with the corresponding file class of processes. The bits are contained in
the file mode, as described in stat (5). The detailed usage of the file permission bits in
access decisions is described in file access permissions.
PIC See position-independent code.
HP-UX 11i Version 2: August 2003 − 14 − Hewlett-Packard Company Section 9−−15