man-pages/man1p/ls.1p

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.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
.TH "LS" 1P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\" ls
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.SH NAME
ls \- list directory contents
.SH SYNOPSIS
.LP
\fBls\fP \fB[\fP\fB-CFRacdilqrtu1\fP\fB][\fP\fB-H | -L\fP
\fB][\fP\fB-fgmnopsx\fP\fB][\fP\fIfile\fP\fB...\fP\fB]\fP
.SH DESCRIPTION
.LP
For each operand that names a file of a type other than directory
or symbolic link to a directory, \fIls\fP shall write the
name of the file as well as any requested, associated information.
For each operand that names a file of type directory, \fIls\fP
shall write the names of files contained within the directory as well
as any requested, associated information. If one of the
\fB-d\fP, \fB-F\fP, or \fB-l\fP options are specified, and one of
the \fB-H\fP or \fB-L\fP options are not specified, for each
operand that names a file of type symbolic link to a directory, \fIls\fP
shall write the name of the file as well as any
requested, associated information. If none of the \fB-d\fP, \fB-F\fP,
or \fB-l\fP options are specified, or the \fB-H\fP or
\fB-L\fP options are specified, for each operand that names a file
of type symbolic link to a directory, \fIls\fP shall write the
names of files contained within the directory as well as any requested,
associated information.
.LP
If no operands are specified, \fIls\fP shall write the contents of
the current directory. If more than one operand is
specified, \fIls\fP shall write non-directory operands first; it shall
sort directory and non-directory operands separately
according to the collating sequence in the current locale.
.LP
The \fIls\fP utility shall detect infinite loops; that is, entering
a previously visited directory that is an ancestor of the
last file encountered. When it detects an infinite loop, \fIls\fP
shall write a diagnostic message to standard error and shall
either recover its position in the hierarchy or terminate.
.SH OPTIONS
.LP
The \fIls\fP utility shall conform to the Base Definitions volume
of IEEE\ Std\ 1003.1-2001, Section 12.2, Utility Syntax Guidelines.
.LP
The following options shall be supported:
.TP 7
\fB-C\fP
Write multi-text-column output with entries sorted down the columns,
according to the collating sequence. The number of text
columns and the column separator characters are unspecified, but should
be adapted to the nature of the output device.
.TP 7
\fB-F\fP
Do not follow symbolic links named as operands unless the \fB-H\fP
or \fB-L\fP options are specified. Write a slash (
\fB'/'\fP ) immediately after each pathname that is a directory, an
asterisk ( \fB'*'\fP ) after each that is executable, a
vertical bar ( \fB'|'\fP ) after each that is a FIFO, and an at sign
( \fB'@'\fP ) after each that is a symbolic link. For
other file types, other symbols may be written.
.TP 7
\fB-H\fP
If a symbolic link referencing a file of type directory is specified
on the command line, \fIls\fP shall evaluate the file
information and file type to be those of the file referenced by the
link, and not the link itself; however, \fIls\fP shall write
the name of the link itself and not the file referenced by the link.
.TP 7
\fB-L\fP
Evaluate the file information and file type for all symbolic links
(whether named on the command line or encountered in a file
hierarchy) to be those of the file referenced by the link, and not
the link itself; however, \fIls\fP shall write the name of the
link itself and not the file referenced by the link. When \fB-L\fP
is used with \fB-l\fP, write the contents of symbolic links in
the long format (see the STDOUT section).
.TP 7
\fB-R\fP
Recursively list subdirectories encountered.
.TP 7
\fB-a\fP
Write out all directory entries, including those whose names begin
with a period ( \fB'.'\fP ). Entries beginning with a
period shall not be written out unless explicitly referenced, the
\fB-a\fP option is supplied, or an implementation-defined
condition shall cause them to be written.
.TP 7
\fB-c\fP
Use time of last modification of the file status information (see
\fI<sys/stat.h>\fP in the System Interfaces volume of IEEE\ Std\ 1003.1-2001)
instead of last modification of the file itself for sorting ( \fB-t\fP)
or writing ( \fB-l\fP).
.TP 7
\fB-d\fP
Do not follow symbolic links named as operands unless the \fB-H\fP
or \fB-L\fP options are specified. Do not treat
directories differently than other types of files. The use of \fB-d\fP
with \fB-R\fP produces unspecified results.
.TP 7
\fB-f\fP
Force each argument to be interpreted as a directory and list the
name found in each slot. This option shall turn off \fB-l\fP,
\fB-t\fP, \fB-s\fP, and \fB-r\fP, and shall turn on \fB-a\fP; the
order is the order in which entries appear in the directory.
.TP 7
\fB-g\fP
The same as \fB-l\fP, except that the owner shall not be written.
.TP 7
\fB-i\fP
For each file, write the file's file serial number (see \fIstat\fP()
in the System
Interfaces volume of IEEE\ Std\ 1003.1-2001).
.TP 7
\fB-l\fP
(The letter ell.) Do not follow symbolic links named as operands unless
the \fB-H\fP or \fB-L\fP options are specified. Write
out in long format (see the STDOUT section). When \fB-l\fP (ell) is
specified, -1 (one) shall be assumed.
.TP 7
\fB-m\fP
Stream output format; list files across the page, separated by commas.
.TP 7
\fB-n\fP
The same as \fB-l\fP, except that the owner's UID and GID numbers
shall be written, rather than the associated character strings.
.TP 7
\fB-o\fP
The same as \fB-l\fP, except that the group shall not be written.
.TP 7
\fB-p\fP
Write a slash ( \fB'/'\fP ) after each filename if that file is a
directory.
.TP 7
\fB-q\fP
Force each instance of non-printable filename characters and <tab>s
to be written as the question-mark ( \fB'?'\fP )
character. Implementations may provide this option by default if the
output is to a terminal device.
.TP 7
\fB-r\fP
Reverse the order of the sort to get reverse collating sequence or
oldest first.
.TP 7
\fB-s\fP
Indicate the total number of file system blocks consumed by each file
displayed. The block size is implementation-defined.
.TP 7
\fB-t\fP
Sort with the primary key being time modified (most recently modified
first) and the secondary key being filename in the
collating sequence.
.TP 7
\fB-u\fP
Use time of last access (see \fI<sys/stat.h>\fP) instead of last modification
of the file for sorting ( \fB-t\fP) or writing ( \fB-l\fP).
.TP 7
\fB-x\fP
The same as \fB-C\fP, except that the multi-text-column output is
produced with entries sorted across, rather than down, the
columns.
.TP 7
\fB-1\fP
(The numeric digit one.) Force output to be one entry per line.
.sp
.LP
Specifying more than one of the options in the following mutually-exclusive
pairs shall not be considered an error: \fB-C\fP
and \fB-l\fP (ell), \fB-m\fP and \fB-l\fP (ell), \fB-x\fP and \fB-l\fP
(ell), \fB-C\fP and \fB-1\fP (one), \fB-H\fP and \fB-L\fP, \fB-c\fP
and \fB-u\fP. The last option
specified in each pair shall determine the output format.
.SH OPERANDS
.LP
The following operand shall be supported:
.TP 7
\fIfile\fP
A pathname of a file to be written. If the file specified is not found,
a diagnostic message shall be output on standard
error.
.sp
.SH STDIN
.LP
Not used.
.SH INPUT FILES
.LP
None.
.SH ENVIRONMENT VARIABLES
.LP
The following environment variables shall affect the execution of
\fIls\fP:
.TP 7
\fICOLUMNS\fP
Determine the user's preferred column position width for writing multiple
text-column output. If this variable contains a
string representing a decimal integer, the \fIls\fP utility shall
calculate how many pathname text columns to write (see
\fB-C\fP) based on the width provided. If \fICOLUMNS\fP is not set
or invalid, an implementation-defined number of column
positions shall be assumed, based on the implementation's knowledge
of the output device. The column width chosen to write the
names of files in any given directory shall be constant. Filenames
shall not be truncated to fit into the multiple text-column
output.
.TP 7
\fILANG\fP
Provide a default value for the internationalization variables that
are unset or null. (See the Base Definitions volume of
IEEE\ Std\ 1003.1-2001, Section 8.2, Internationalization Variables
for
the precedence of internationalization variables used to determine
the values of locale categories.)
.TP 7
\fILC_ALL\fP
If set to a non-empty string value, override the values of all the
other internationalization variables.
.TP 7
\fILC_COLLATE\fP
.sp
Determine the locale for character collation information in determining
the pathname collation sequence.
.TP 7
\fILC_CTYPE\fP
Determine the locale for the interpretation of sequences of bytes
of text data as characters (for example, single-byte as
opposed to multi-byte characters in arguments) and which characters
are defined as printable (character class \fBprint\fP).
.TP 7
\fILC_MESSAGES\fP
Determine the locale that should be used to affect the format and
contents of diagnostic messages written to standard
error.
.TP 7
\fILC_TIME\fP
Determine the format and contents for date and time strings written
by \fIls\fP.
.TP 7
\fINLSPATH\fP
Determine the location of message catalogs for the processing of \fILC_MESSAGES
\&.\fP
.TP 7
\fITZ\fP
Determine the timezone for date and time strings written by \fIls\fP.
If \fITZ\fP is unset or null, an unspecified default
timezone shall be used.
.sp
.SH ASYNCHRONOUS EVENTS
.LP
Default.
.SH STDOUT
.LP
The default format shall be to list one entry per line to standard
output; the exceptions are to terminals or when one of the
\fB-C\fP, \fB-m\fP, or \fB-x\fP options is specified. If the
output is to a terminal, the format is implementation-defined.
.LP
When \fB-m\fP is specified, the format used shall be:
.sp
.RS
.nf
\fB"%s, %s, ...\\n", <\fP\fIfilename1\fP\fB>, <\fP\fIfilename2\fP\fB>
\fP
.fi
.RE
.LP
where the largest number of filenames shall be written without exceeding
the length of the line.
.LP
If the \fB-i\fP option is specified, the file's file serial number
(see \fI<sys/stat.h>\fP) shall be written in the following format
before any other output for
the corresponding entry:
.sp
.RS
.nf
\fB%u ", <\fP\fIfile serial number\fP\fB>
\fP
.fi
.RE
.LP
If the \fB-l\fP option is specified without \fB-L\fP, the following
information shall be written:
.sp
.RS
.nf
\fB"%s %u %s %s %u %s %s\\n", <\fP\fIfile mode\fP\fB>, <\fP\fInumber of links\fP\fB>,
<\fP\fIowner name\fP\fB>, <\fP\fIgroup name\fP\fB>, <\fP\fInumber of bytes in the file\fP\fB>,
<\fP\fIdate and time\fP\fB>, <\fP\fIpathname\fP\fB>
\fP
.fi
.RE
.LP
If the file is a symbolic link, this information shall be about the
link itself and the <\fIpathname\fP> field shall be
of the form:
.sp
.RS
.nf
\fB"%s -> %s", <\fP\fIpathname of link\fP\fB>, <\fP\fIcontents of link\fP\fB>
\fP
.fi
.RE
.LP
If both \fB-l\fP and \fB-L\fP are specified, the following information
shall be written:
.sp
.RS
.nf
\fB"%s %u %s %s %u %s %s\\n", <\fP\fIfile mode\fP\fB>, <\fP\fInumber of links\fP\fB>,
<\fP\fIowner name\fP\fB>, <\fP\fIgroup name\fP\fB>, <\fP\fInumber of bytes in the file\fP\fB>,
<\fP\fIdate and time\fP\fB>, <\fP\fIpathname of link\fP\fB>
\fP
.fi
.RE
.LP
where all fields except <\fIpathname of link\fP> shall be for the
file resolved from the symbolic link.
.LP
The \fB-g\fP, \fB-n\fP, and \fB-o\fP options use the same format as
\fB-l\fP, but with omitted items and their associated
<blank>s. See the OPTIONS section.
.LP
In both the preceding \fB-l\fP forms, if <\fIowner name\fP> or <\fIgroup
name\fP> cannot be determined, or if
\fB-n\fP is given, they shall be replaced with their associated
numeric values using the format \fB%u\fP .
.LP
The <\fIdate\ and\ time\fP> field shall contain the appropriate date
and timestamp of when the file was last
modified. In the POSIX locale, the field shall be the equivalent of
the output of the following \fIdate\fP command:
.sp
.RS
.nf
\fBdate "+%b %e %H:%M"
\fP
.fi
.RE
.LP
if the file has been modified in the last six months, or:
.sp
.RS
.nf
\fBdate "+%b %e %Y"
\fP
.fi
.RE
.LP
(where two <space>s are used between \fB%e\fP and \fB%Y\fP ) if the
file has not been modified in the last six
months or if the modification date is in the future, except that,
in both cases, the final <newline> produced by \fIdate\fP shall not
be included and the output shall be as if the \fIdate\fP command were
executed at the time of the last modification date of the file rather
than
the current time. When the \fILC_TIME\fP locale category is not set
to the POSIX locale, a different format and order of
presentation of this field may be used.
.LP
If the file is a character special or block special file, the size
of the file may be replaced with implementation-defined
information associated with the device in question.
.LP
If the pathname was specified as a \fIfile\fP operand, it shall be
written as specified.
.LP
The file mode written under the \fB-l\fP, \fB-g\fP, \fB-n\fP, and
\fB-o\fP options shall consist of the following format:
.sp
.RS
.nf
\fB"%c%s%s%s%c", <\fP\fIentry type\fP\fB>, <\fP\fIowner permissions\fP\fB>,
<\fP\fIgroup permissions\fP\fB>, <\fP\fIother permissions\fP\fB>,
<\fP\fIoptional alternate access method flag\fP\fB>
\fP
.fi
.RE
.LP
The <\fIoptional\ alternate\ access\ method\ flag\fP> shall be a single
<space> if there is no
alternate or additional access control method associated with the
file; otherwise, a printable character shall be used.
.LP
The <\fIentry\ type\fP> character shall describe the type of file,
as follows:
.TP 7
\fBd\fP
Directory.
.TP 7
\fBb\fP
Block special file.
.TP 7
\fBc\fP
Character special file.
.TP 7
\fBl\fP\ (ell)
Symbolic link.
.TP 7
\fBp\fP
FIFO.
.TP 7
\fB-\fP
Regular file.
.sp
.LP
Implementations may add other characters to this list to represent
other implementation-defined file types.
.LP
The next three fields shall be three characters each:
.TP 7
<\fIowner permissions\fP>
.sp
Permissions for the file owner class (see the Base Definitions volume
of IEEE\ Std\ 1003.1-2001, Section 4.4, File Access Permissions).
.TP 7
<\fIgroup permissions\fP>
.sp
Permissions for the file group class.
.TP 7
<\fIother permissions\fP>
.sp
Permissions for the file other class.
.sp
.LP
Each field shall have three character positions:
.IP " 1." 4
If \fB'r'\fP, the file is readable; if \fB'-'\fP, the file is not
readable.
.LP
.IP " 2." 4
If \fB'w'\fP, the file is writable; if \fB'-'\fP, the file is not
writable.
.LP
.IP " 3." 4
The first of the following that applies:
.TP 7
\fBS\fP
.RS
If in <\fIowner\ permissions\fP>, the file is not executable and set-user-ID
mode is set. If in
<\fIgroup\ permissions\fP>, the file is not executable and set-group-ID
mode is set.
.RE
.TP 7
\fBs\fP
.RS
If in <\fIowner\ permissions\fP>, the file is executable and set-user-ID
mode is set. If in
<\fIgroup\ permissions\fP>, the file is executable and set-group-ID
mode is set.
.RE
.TP 7
\fBT\fP
.RS
If in <\fIother\ permissions\fP> and the file is a directory, search
permission is not granted to others, and the
restricted deletion flag is set.
.RE
.TP 7
\fBt\fP
.RS
If in <\fIother\ permissions\fP> and the file is a directory, search
permission is granted to others, and the restricted
deletion flag is set.
.RE
.TP 7
\fBx\fP
.RS
The file is executable or the directory is searchable.
.RE
.TP 7
\fB-\fP
.RS
None of the attributes of \fB'S'\fP, \fB's'\fP, \fB'T'\fP, \fB't'\fP,
or \fB'x'\fP applies.
.RE
.sp
.LP
Implementations may add other characters to this list for the third
character position. Such additions shall, however, be
written in lowercase if the file is executable or searchable, and
in uppercase if it is not.
.LP
.LP
If any of the \fB-l\fP, \fB-g\fP, \fB-n\fP, \fB-o\fP, or \fB-s\fP
options is specified, each list of files within the directory shall
be preceded by a status line indicating the number
of file system blocks occupied by files in the directory in 512-byte
units, rounded up to the next integral number of units, if
necessary. In the POSIX locale, the format shall be:
.sp
.RS
.nf
\fB"total %u\\n", <\fP\fInumber of units in the directory\fP\fB>
\fP
.fi
.RE
.LP
If more than one directory, or a combination of non-directory files
and directories are written, either as a result of
specifying multiple operands, or the \fB-R\fP option, each list of
files within a directory shall be preceded by:
.sp
.RS
.nf
\fB"\\n%s:\\n", <\fP\fIdirectory name\fP\fB>
\fP
.fi
.RE
.LP
If this string is the first thing to be written, the first <newline>
shall not be written. This output shall precede the
number of units in the directory.
.LP
If the \fB-s\fP option is given, each file shall be written with the
number of blocks used by the file. Along with \fB-C\fP,
\fB-1\fP, \fB-m\fP, or \fB-x\fP, the number and a <space> shall precede
the filename; with \fB-g\fP, \fB-l\fP,
\fB-n\fP, or \fB-o\fP, they shall precede each line describing a file.
.SH STDERR
.LP
The standard error shall be used only for diagnostic messages.
.SH OUTPUT FILES
.LP
None.
.SH EXTENDED DESCRIPTION
.LP
None.
.SH EXIT STATUS
.LP
The following exit values shall be returned:
.TP 7
\ 0
Successful completion.
.TP 7
>0
An error occurred.
.sp
.SH CONSEQUENCES OF ERRORS
.LP
Default.
.LP
\fIThe following sections are informative.\fP
.SH APPLICATION USAGE
.LP
Many implementations use the equal sign ( \fB'='\fP ) to denote sockets
bound to the file system for the \fB-F\fP option.
Similarly, many historical implementations use the \fB's'\fP character
to denote sockets as the entry type characters for the
\fB-l\fP option.
.LP
It is difficult for an application to use every part of the file modes
field of \fIls\fP \fB-l\fP in a portable manner.
Certain file types and executable bits are not guaranteed to be exactly
as shown, as implementations may have extensions.
Applications can use this field to pass directly to a user printout
or prompt, but actions based on its contents should generally
be deferred, instead, to the \fItest\fP utility.
.LP
The output of \fIls\fP (with the \fB-l\fP and related options) contains
information that logically could be used by utilities
such as \fIchmod\fP and \fItouch\fP to restore files
to a known state. However, this information is presented in a format
that cannot be used directly by those utilities or be easily
translated into a format that can be used. A character has been added
to the end of the permissions string so that applications at
least have an indication that they may be working in an area they
do not understand instead of assuming that they can translate the
permissions string into something that can be used. Future issues
or related documents may define one or more specific characters
to be used based on different standard additional or alternative access
control mechanisms.
.LP
As with many of the utilities that deal with filenames, the output
of \fIls\fP for multiple files or in one of the long listing
formats must be used carefully on systems where filenames can contain
embedded white space. Systems and system administrators
should institute policies and user training to limit the use of such
filenames.
.LP
The number of disk blocks occupied by the file that it reports varies
depending on underlying file system type, block size units
reported, and the method of calculating the number of blocks. On some
file system types, the number is the actual number of blocks
occupied by the file (counting indirect blocks and ignoring holes
in the file); on others it is calculated based on the file size
(usually making an allowance for indirect blocks, but ignoring holes).
.SH EXAMPLES
.LP
An example of a small directory tree being fully listed with \fIls\fP
\fB-laRF\ a\fP in the POSIX locale:
.sp
.RS
.nf
\fBtotal 11
drwxr-xr-x 3 hlj prog 64 Jul 4 12:07 ./
drwxrwxrwx 4 hlj prog 3264 Jul 4 12:09 ../
drwxr-xr-x 2 hlj prog 48 Jul 4 12:07 b/
-rwxr--r-- 1 hlj prog 572 Jul 4 12:07 foo*
.sp
a/b:
total 4
drwxr-xr-x 2 hlj prog 48 Jul 4 12:07 ./
drwxr-xr-x 3 hlj prog 64 Jul 4 12:07 ../
-rw-r--r-- 1 hlj prog 700 Jul 4 12:07 bar
\fP
.fi
.RE
.SH RATIONALE
.LP
Some historical implementations of the \fIls\fP utility show all entries
in a directory except dot and dot-dot when a superuser
invokes \fIls\fP without specifying the \fB-a\fP option. When "normal"
users invoke \fIls\fP without specifying \fB-a\fP,
they should not see information about any files with names beginning
with a period unless they were named as \fIfile\fP
operands.
.LP
Implementations are expected to traverse arbitrary depths when processing
the \fB-R\fP option. The only limitation on depth
should be based on running out of physical storage for keeping track
of untraversed directories.
.LP
The \fB-1\fP (one) option was historically found in BSD and BSD-derived
implementations only. It is required in this volume of
IEEE\ Std\ 1003.1-2001 so that conforming applications might ensure
that output is one entry per line, even if the output
is to a terminal.
.LP
Generally, this volume of IEEE\ Std\ 1003.1-2001 is silent about what
happens when options are given multiple times. In
the cases of \fB-C\fP, \fB-l\fP, and \fB-1\fP, however, it does specify
the results of these overlapping options. Since
\fIls\fP is one of the most aliased commands, it is important that
the implementation perform intuitively. For example, if the
alias were:
.sp
.RS
.nf
\fBalias ls="ls -C"
\fP
.fi
.RE
.LP
and the user typed \fIls\fP \fB-1\fP, single-text-column output should
result, not an error.
.LP
The BSD \fIls\fP provides a \fB-A\fP option (like \fB-a\fP, but dot
and dot-dot are not written out). The small difference
from \fB-a\fP did not seem important enough to require both.
.LP
Implementations may make \fB-q\fP the default for terminals to prevent
trojan horse attacks on terminals with special escape
sequences. This is not required because:
.IP " *" 3
Some control characters may be useful on some terminals; for example,
a system might write them as \fB"\\001"\fP or
\fB"^A"\fP .
.LP
.IP " *" 3
Special behavior for terminals is not relevant to applications portability.
.LP
.LP
An early proposal specified that the optional alternate access method
flag had to be \fB'+'\fP if there was an alternate
access method used on the file or <space> if there was not. This was
changed to be <space> if there is not and a single
printable character if there is. This was done for three reasons:
.IP " 1." 4
There are historical implementations using characters other than \fB'+'\fP
\&.
.LP
.IP " 2." 4
There are implementations that vary this character used in that position
to distinguish between various alternate access methods
in use.
.LP
.IP " 3." 4
The standard developers did not want to preclude future specifications
that might need a way to specify more than one alternate
access method.
.LP
.LP
Nonetheless, implementations providing a single alternate access method
are encouraged to use \fB'+'\fP .
.LP
In an early proposal, the units used to specify the number of blocks
occupied by files in a directory in an \fIls\fP \fB-l\fP
listing were implementation-defined. This was because BSD systems
have historically used 1024-byte units and System V systems have
historically used 512-byte units. It was pointed out by BSD developers
that their system has used 512-byte units in some places and
1024-byte units in other places. (System V has consistently used 512.)
Therefore, this volume of IEEE\ Std\ 1003.1-2001
usually specifies 512. Future releases of BSD are expected to consistently
provide 512 bytes as a default with a way of specifying
1024-byte units where appropriate.
.LP
The <\fIdate\ and\ time\fP> field in the \fB-l\fP format is specified
only for the POSIX locale. As noted, the
format can be different in other locales. No mechanism for defining
this is present in this volume of
IEEE\ Std\ 1003.1-2001, as the appropriate vehicle is a messaging
system; that is, the format should be specified as a
"message".
.SH FUTURE DIRECTIONS
.LP
The \fB-s\fP uses implementation-defined units and cannot be used
portably; it may be withdrawn in a future version.
.SH SEE ALSO
.LP
\fIchmod\fP(), \fIfind\fP, the System Interfaces volume of
IEEE\ Std\ 1003.1-2001, \fIstat\fP(), the Base Definitions volume
of
IEEE\ Std\ 1003.1-2001, \fI<sys/stat.h>\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .