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diff --git a/man-pages-posix-2003/man1p/df.1p b/man-pages-posix-2003/man1p/df.1p new file mode 100644 index 0000000..f62589b --- /dev/null +++ b/man-pages-posix-2003/man1p/df.1p @@ -0,0 +1,301 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "DF" 1P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" df +.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 +df \- report free disk space +.SH SYNOPSIS +.LP +\fBdf\fP \fB[\fP\fB-k\fP\fB][\fP\fB-P|-t\fP\fB][\fP\fIfile\fP\fB...\fP\fB]\fP\fB\fP +.SH DESCRIPTION +.LP +The \fIdf\fP utility shall write the amount of available space and +file slots for file systems on which the invoking user has appropriate +read access. File systems shall be specified +by the \fIfile\fP operands; when none are specified, information shall +be written for all file systems. The format of the default +output from \fIdf\fP is unspecified, but all space figures are reported +in 512-byte units, unless the \fB-k\fP option is +specified. This output shall contain at least the file system names, +amount of available space on each of these file systems, +\ and the number of free file slots, or \fIinodes\fP, available; when +\fB-t\fP is specified, the output shall contain the +total allocated space as well. +.SH OPTIONS +.LP +The \fIdf\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-k\fP +Use 1024-byte units, instead of the default 512-byte units, when writing +space figures. +.TP 7 +\fB-P\fP +Produce output in the format described in the STDOUT section. +.TP 7 +\fB-t\fP +Include total allocated-space figures in the output. +.sp +.SH OPERANDS +.LP +The following operand shall be supported: +.TP 7 +\fIfile\fP +A pathname of a file within the hierarchy of the desired file system. +If a file other than a FIFO, a regular file, a directory, +\ or a special file representing the device containing the file system +(for example, \fB/dev/dsk/0s1\fP) is specified, the results are unspecified. +Otherwise, \fIdf\fP shall write +the amount of free space in the file system containing the specified +\fIfile\fP operand. +.sp +.SH STDIN +.LP +Not used. +.SH INPUT FILES +.LP +None. +.SH ENVIRONMENT VARIABLES +.LP +The following environment variables shall affect the execution of +\fIdf\fP: +.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_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). +.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 and +informative messages written to standard output. +.TP 7 +\fINLSPATH\fP +Determine the location of message catalogs for the processing of \fILC_MESSAGES +\&.\fP +.sp +.SH ASYNCHRONOUS EVENTS +.LP +Default. +.SH STDOUT +.LP +When both the \fB-k\fP and \fB-P\fP options are specified, the following +header line shall be written (in the POSIX +locale): +.sp +.RS +.nf + +\fB"Filesystem 1024-blocks Used Available Capacity Mounted on\\n" +\fP +.fi +.RE +.LP +When the \fB-P\fP option is specified without the \fB-k\fP option, +the following header line shall be written (in the POSIX +locale): +.sp +.RS +.nf + +\fB"Filesystem 512-blocks Used Available Capacity Mounted on\\n" +\fP +.fi +.RE +.LP +The implementation may adjust the spacing of the header line and the +individual data lines so that the information is presented +in orderly columns. +.LP +The remaining output with \fB-P\fP shall consist of one line of information +for each specified file system. These lines shall +be formatted as follows: +.sp +.RS +.nf + +\fB"%s %d %d %d %d%% %s\\n", <\fP\fIfile system name\fP\fB>, <\fP\fItotal space\fP\fB>, + <\fP\fIspace used\fP\fB>, <\fP\fIspace free\fP\fB>, <\fP\fIpercentage used\fP\fB>, + <\fP\fIfile system root\fP\fB> +\fP +.fi +.RE +.LP +In the following list, all quantities expressed in 512-byte units +(1024-byte when \fB-k\fP is specified) shall be rounded up to +the next higher unit. The fields are: +.TP 7 +<\fIfile\ system\ name\fP> +.sp +The name of the file system, in an implementation-defined format. +.TP 7 +<\fItotal\ space\fP> +The total size of the file system in 512-byte units. The exact meaning +of this figure is implementation-defined, but should +include <\fIspace\ used\fP>, <\fIspace\ free\fP>, plus any space reserved +by the system not normally +available to a user. +.TP 7 +<\fIspace\ used\fP> +The total amount of space allocated to existing files in the file +system, in 512-byte units. +.TP 7 +<\fIspace\ free\fP> +The total amount of space available within the file system for the +creation of new files by unprivileged users, in 512-byte +units. When this figure is less than or equal to zero, it shall not +be possible to create any new files on the file system without +first deleting others, unless the process has appropriate privileges. +The figure written may be less than zero. +.TP 7 +<\fIpercentage\ used\fP> +.sp +The percentage of the normally available space that is currently allocated +to all files on the file system. This shall be +calculated using the fraction: +.sp +.RS +.nf + +\fB<\fP\fIspace used\fP\fB>/( <\fP\fIspace used\fP\fB>+ <\fP\fIspace free\fP\fB>) +\fP +.fi +.RE +.LP +expressed as a percentage. This percentage may be greater than 100 +if <\fIspace\ free\fP> is less than zero. The +percentage value shall be expressed as a positive integer, with any +fractional result causing it to be rounded to the next highest +integer. +.TP 7 +<\fIfile\ system\ root\fP> +.sp +The directory below which the file system hierarchy appears. +.sp +.LP +The output format is unspecified when \fB-t\fP is used. +.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 +On most systems, the "name of the file system, in an implementation-defined +format" is the special file on which the file +system is mounted. +.LP +On large file systems, the calculation specified for percentage used +can create huge rounding errors. +.SH EXAMPLES +.IP " 1." 4 +The following example writes portable information about the \fB/usr\fP +file system: +.sp +.RS +.nf + +\fBdf -P /usr +\fP +.fi +.RE +.LP +.IP " 2." 4 +Assuming that \fB/usr/src\fP is part of the \fB/usr\fP file system, +the following produces the same output as the previous +example: +.sp +.RS +.nf + +\fBdf -P /usr/src +\fP +.fi +.RE +.LP +.SH RATIONALE +.LP +The behavior of \fIdf\fP with the \fB-P\fP option is the default action +of the 4.2 BSD \fIdf\fP utility. The uppercase +\fB-P\fP was selected to avoid collision with a known industry extension +using \fB-p\fP. +.LP +Historical \fIdf\fP implementations vary considerably in their default +output. It was therefore necessary to describe the +default output in a loose manner to accommodate all known historical +implementations and to add a portable option ( \fB-P\fP) to +provide information in a portable format. +.LP +The use of 512-byte units is historical practice and maintains compatibility +with \fIls\fP +and other utilities in this volume of IEEE\ Std\ 1003.1-2001. This +does not mandate that the file system itself be based on +512-byte blocks. The \fB-k\fP option was added as a compromise measure. +It was agreed by the standard developers that 512 bytes +was the best default unit because of its complete historical consistency +on System V (\fIversus\fP the mixed 512/1024-byte usage +on BSD systems), and that a \fB-k\fP option to switch to 1024-byte +units was a good compromise. Users who prefer the more logical +1024-byte quantity can easily alias \fIdf\fP to \fIdf\fP \fB-k\fP +without breaking many historical scripts relying on the +512-byte units. +.LP +It was suggested that \fIdf\fP and the various related utilities be +modified to access a \fIBLOCKSIZE\fP environment variable +to achieve consistency and user acceptance. Since this is not historical +practice on any system, it is left as a possible area for +system extensions and will be re-evaluated in a future version if +it is widely implemented. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIfind\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 . |