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

t
glossary(9) glossary(9)
Two benefits are realized by terminal affiliation. First, all signals sent from the terminal are sent to all
processes in the terminal group. Second, all processes in the terminal group can perform I/O to/from the
generic terminal driver /dev/tty, which automatically selects the affiliated terminal.
Terminal affiliation is broken with a terminal group when the process group leader terminates, after which
the hangup signal is sent to all processes remaining in the process group. Also, if a process (which is not a
process group leader) in the terminal group becomes a process group leader via the setpgrp(2) system call,
its terminal affiliation is broken.
See process group, process group leader, terminal group, and setpgrp(2).
terminal device
See terminal.
text file
A file that contains characters organized into one or more lines. The lines cannot contain NUL characters,
and none can exceed
LINE_MAX bytes in length including the terminating newline character. Although
neither the kernel nor the C language implementation distinguishes between text files and binary files (see
ANSI C Standard X3-159-19xx), many utilities behave predictably only when operating on text files.
tty
Originally, an abbreviation for teletypewriter; now, generally, a terminal.
upshifting
The conversion of a lowercase character to its uppercase representation.
user ID
Each system user is identified by an integer known as a user ID, which is in the range of zero to
UID_MAX, inclusive. Depending on how the user is identified with a process, a user ID value is referred
to as a real user ID,aneffective user ID,orasaved user ID.
UTC
See Epoch.
utility
An executable file, which might contain executable object code (that is, a program), or a list of commands
to execute in a given order (that is, a shell script). You can write your own utilities, either as executable
programs or shell scripts (which are written in the shell programming language).
volume number
Part of an address used for devices. A number whose meaning is software- and device-dependent, but
which is often used to specify a particular volume on a multivolume disk drive. See the System Adminis-
trator manuals supplied with your system for details.
whitespace
One or more characters which, when displayed, cause a movement of the cursor or print head, but do not
result in the display of any visible graphic. The whitespace characters in the ASCII code set are space, tab,
newline, form feed, carriage return, and vertical tab. A particular command or routine might interpret
some, but not necessarily all, whitespace characters as delimiters for fields, words, or command options.
working directory
Each process has associated with it the concept of a current working directory. For a shell, this appears as
the directory in which you currently "reside". This is the directory in which relative path name (that is, a
path name that does not begin with
/) searches begin. It is sometimes referred to as the current direc-
tory, or the current working directory.
zombie process
The name given to a process which terminates for any reason, but whose parent process has not yet waited
for it to terminate (via wait(2)). The process which terminated continues to occupy a slot in the process
table until its parent process waits for it. Because it has terminated, however, there is no other space allo-
cated to it either in user or kernel space. It is therefore a relatively harmless occurrence which will rectify
itself the next time its parent process waits. The ps(1) command lists zombie processes as defunct.
270 Hewlett-Packard Company − 25 − HP-UX 11i Version 3: February 2007