HP-UX Reference (11i v2 03/08) - 5 Miscellaneous Topics, 7 Device (Special) Files, 9 General Information, Index (vol 9)

f
glossary(9) glossary(9)
Read, write, and execute/search permissions on a file are granted to a process if any of
the following conditions are met:
• The process’s effective user ID is superuser.
• The process’s effective user ID matches the user ID of the owner of the file and
the appropriate access bit of the owner portion (0700) of the file mode is set.
• The process’s effective user ID does not match the user ID of the owner of the
file, and either the process’s effective group ID matches the group ID of the
file, or the group ID of the file is in the process’s group access list, and the
appropriate access bit of the group portion (070) of the file mode is set.
• The process’s effective user ID does not match the user ID of the owner of the
file, and the process’s effective group ID does not match the group ID of the
file, and the group ID of the file is not in the process’s group access list, and the
appropriate access bit of the ‘‘other’’ portion (07) of the file mode is set.
Otherwise, the corresponding permissions are denied.
file descriptor
A small unique, per-process, nonnegative integer identifier that is used to refer to a file
opened for reading and/or writing. Each file descriptor refers to exactly one open file
description.
A file descriptor is obtained through system calls such as creat(2), fcntl (2), open(2),
pipe(2), or dup(2). The file descriptor is used as an argument by calls such as read(2),
write(2), ioctl (2), and close(2).
The value of a file descriptor has a range from 0 to one less than the system-defined
maximum. The system-defined maximum is the value
NOFILE in <sys/param.h>
.
file group class
A process is in the file group class of a file if the process is not the file owner class
and if the effective group ID or one of the supplementary group IDs of the process
matches the group ID associated with the file.
file hierarchy The collection of one or more file systems available on a system. All files in these file
systems are organized in a single hierarchical structure in which all of the nonterminal
nodes are directories. Because multiple links can refer to the same file, the directory
is properly described as a directed graph.
file name A string of up to 14 bytes (or 255 bytes on file systems that support long file names) used
to refer to an ordinary file, special file, or directory. The byte values NUL (null) and
slash (
/) cannot be used as characters in a file name. Note that it is generally unwise to
use *, ?, ,, [,or] as part of file names because the shell attaches special meaning to
these characters (see sh(1), csh(1), or ksh(1)). Avoid beginning a file name with
-, +,or
=, because to some programs, these characters signify that a command argument follows.
A file name is sometimes called a path name component. Although permitted, it is
inadvisable to use characters that do not have a printable graphic on the hardware you
commonly use, or that are likely to confuse your terminal.
file name portability
File names should be constructed from the portable file name character set because
the use of other characters can be confusing or ambiguous in certain contexts.
file offset The file offset specifies the position in the file where the next I/O operation begins. Each
open file description associated with either a regular file or special file has a file
offset. There is no file offset specified for a pipe or FIFO.
file other class
A process is in the file other class if the process is not in the file owner class or file
group class.
file owner class
A process is in the file owner class if the effective user ID of the process matches the
user ID of the file.
file permission bits
See permission bits.
Section 9−−8 Hewlett-Packard Company − 7 − HP-UX 11i Version 2: August 2003