1 '\" Copyright (C) 1998-2023 Free Software Foundation, Inc. 2 '\" 3 '\" This is free software. You may redistribute copies of it under the terms 4 '\" of the GNU General Public License <https://www.gnu.org/licenses/gpl.html>. 5 '\" There is NO WARRANTY, to the extent permitted by law. 6 [NAME] 7 df \- report file system space usage 8 [DESCRIPTION] 9 This manual page 10 documents the GNU version of 11 .BR df . 12 .B df 13 displays the amount of space available on the file system 14 containing each file name argument. If no file name is given, the 15 space available on all currently mounted file systems is shown. 16 Space is shown in 1K blocks by default, unless the environment 17 variable POSIXLY_CORRECT is set, in which case 512-byte blocks are 18 used. 19 .PP 20 If an argument is the absolute file name of a device node containing a 21 mounted file system, 22 .B df 23 shows the space available on that file system rather than on the 24 file system containing the device node. This version of 25 .B df 26 cannot show the space available on unmounted file systems, because on 27 most kinds of systems doing so requires non-portable intimate 28 knowledge of file system structures. 29 .SH OPTIONS 30